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Post by whiskeycharlie242 on Mar 14, 2019 11:42:28 GMT -5
I recently decided to jump in to classic radio pool and pick up an SBE Trinidad, one of my favorite radios I owned back in the day.
I decided to watch and wait for the right one to come along and was pleased to pick up a mint example for little money on eBay from an honest seller in Idaho. The radio was even better than expected - clean and fresh with minimal signs of use and age related wear.
Of course, I took the case off to check things out and dust things off, although there literally was none. The dichromate was still lustrous like new and all the screws seemed to have been untouched.
I also wired up a beautiful D-104 that I picked up separately and checked her out.
Everything was more or less working as it should, with about 3.5 watts out, which is pretty typical for a stock radio that had never been touched. A few channels were off frequency by about 2 KHz, which I’ll need to address long term, but I was pretty happy overall.
Some of the switches were a little dirty, so I cleaned them with contact cleaner, which restored them to perfect working order. Or so it seemed.
A week later the front panel switches began to mechanically fail. The switches are a DPDT type that are screw mounted with a rocker action lever that has a brushed aluminum cover that makes them more elegant than the usual black SBE switches found on other models.
Turns out that the plastic rockers inside the switch did not like the contact cleaner so much and broke at their pivot point, which were probably already somewhat brittle from age. One by one, three of four failed in the same way.
I disassembled the rig to get at the switches to see what had happened and hopefully repair them, but the plastic is a type that doesn’t bind with superglue, so no luck gluing them back together.
So, back to Google and eBay to find parts. No such luck finding the switches. Only SBE used them and no other radios than the Trinidad, Trinidad II or Console V has them. Yikes!
But lo and behold, another Trinidad for about the same price appeared, so I bought it for parts. I just couldn’t bear having a mint radio left for dead because I made a foolish mistake in using contact cleaner.
The second rig arrived as advertised, i.e. non-working condition. The seller said the radio did not power up, so I figured it to be a good donor for switches and future spares. It also came with an original manual and stock mike, which you don’t see too often anymore.
Tucked in the manual was a separate document listing all the SBE certified service stations, which is quite a trip down memory lane. Also enclosed was an Antenna Specialist’s warranty card showing the purchase of an M-400 Starduster in January of ‘77. No doubt this was a decent base setup for its time.
So I plug ol’ number two in and nothing. Check the fuses, both good. Hook it up to 12 volts and it still seems dead.
But the patient wasn’t dead, just playing possum. With two burned out bulbs, no antenna hooked up and the ANL on, the radio was completely silent. I turned the dirty volume switch a few times and heard static. I plugged it back into AC and it continued to work.
So now I have a dilemma. Sacrifice another working Trinidad to repair the much nicer Trinidad that had few issues or fix up the lesser one, which seems to have other issues.
Unless I can find the switches somewhere, one must die so the other can live.
What say you? Any SBE junkies out there that have switches to part with?
Signed,
Trini’s Dad
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Sandbagger
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Post by Sandbagger on Mar 14, 2019 18:13:57 GMT -5
I recently decided to jump in to classic radio pool and pick up an SBE Trinidad, one of my favorite radios I owned back in the day. I decided to watch and wait for the right one to come along and was pleased to pick up a mint example for little money on eBay from an honest seller in Idaho. The radio was even better than expected - clean and fresh with minimal signs of use and age related wear. Of course, I took the case off to check things out and dust things off, although there literally was none. The dichromate was still lustrous like new and all the screws seemed to have been untouched. I also wired up a beautiful D-104 that I picked up separately and checked her out. Everything was more or less working as it should, with about 3.5 watts out, which is pretty typical for a stock radio that had never been touched. A few channels were off frequency by about 2 KHz, which I’ll need to address long term, but I was pretty happy overall. Some of the switches were a little dirty, so I cleaned them with contact cleaner, which restored them to perfect working order. Or so it seemed. A week later the front panel switches began to mechanically fail. The switches are a DPDT type that are screw mounted with a rocker action lever that has a brushed aluminum cover that makes them more elegant than the usual black SBE switches found on other models. Turns out that the plastic rockers inside the switch did not like the contact cleaner so much and broke at their pivot point, which were probably already somewhat brittle from age. One by one, three of four failed in the same way. I disassembled the rig to get at the switches to see what had happened and hopefully repair them, but the plastic is a type that doesn’t bind with superglue, so no luck gluing them back together. So, back to Google and eBay to find parts. No such luck finding the switches. Only SBE used them and no other radios than the Trinidad, Trinidad II or Console V has them. Yikes! But lo and behold, another Trinidad for about the same price appeared, so I bought it for parts. I just couldn’t bear having a mint radio left for dead because I made a foolish mistake in using contact cleaner. The second rig arrived as advertised, i.e. non-working condition. The seller said the radio did not power up, so I figured it to be a good donor for switches and future spares. It also came with an original manual and stock mike, which you don’t see too often anymore. Tucked in the manual was a separate document listing all the SBE certified service stations, which is quite a trip down memory lane. Also enclosed was an Antenna Specialist’s warranty card showing the purchase of an M-400 Starduster in January of ‘77. No doubt this was a decent base setup for its time. So I plug ol’ number two in and nothing. Check the fuses, both good. Hook it up to 12 volts and it still seems dead. But the patient wasn’t dead, just playing possum. With two burned out bulbs, no antenna hooked up and the ANL on, the radio was completely silent. I turned the dirty volume switch a few times and heard static. I plugged it back into AC and it continued to work. So now I have a dilemma. Sacrifice another working Trinidad to repair the much nicer Trinidad that had few issues or fix up the lesser one, which seems to have other issues. Unless I can find the switches somewhere, one must die so the other can live. What say you? Any SBE junkies out there that have switches to part with? Signed, Trini’s Dad Lesson learned, not all contact cleaners are created equal, and many will dissolve plastic. Most of the guys on here swear by De-Oxit ( caig.com/deoxit-d-series/). It does the job and doesn't seem to hurt the plastics. As for which 'dad to restore, I would pick the one in newest, cleanest condition. I am in need of those bat handle switches as well. My "Frankendad" grumpy.proboards.com/post/53224 project started off with a less than minty Trinidad (The older "A" version), which I transplanted a 40 channel radio into. But the first 2 switches were broken off, which is a bit of a bummer, and replacements are not easy to find. I have another Trinidad, but that's my vintage radio. It's not super clean either, but I'm keeping that one as original as possible, and there's no way I'd sacrifice those switches. I'll have to wait for a parts radio to appear. But that's always a dilemma for me as I'm always tempted to restore the parts radio too. It would have to be a complete basket case...... |
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Sandbagger
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Post by Sandbagger on May 2, 2019 14:15:56 GMT -5
Any news on the Trinidad front? Progress/Congress?
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Post by whiskeycharlie242 on May 2, 2019 15:56:47 GMT -5
Any news on the Trinidad front? Progress/Congress? I’ve boxed them up for now because it stresses me out to look at them. If someone had time and interest in swapping the switches for me, there might be a good parts radio in it for them. Just sayin’... On a different note, it seems that Es is starting to run. I tripped onto a small group of regulars on 27.425 AM early this morning. I don’t think they were aware the skip was rolling. Signals were 7 to 9+. I assumed that their signals were shifting polarization to horizontal, bringing my indoor horizontal wire dipole to life They could not hear me but it was nice to hear a group chatting on AM. First AM I’ve heard out here at all. Based on what they were talking about, I think they were in SoCal or western Arizona. The band was only open for about 10 minutes or so and then they faded away. Also built an experimental half-wave sleeved vertical dipole for the boat (encased in PVC to avoid shorts in the rigging) that can be hoisted about 30 feet above the water but need to strengthen it in the middle where it flexes before I can try it out and tune it. |
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Sandbagger
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Post by Sandbagger on May 2, 2019 17:06:39 GMT -5
Any news on the Trinidad front? Progress/Congress? I’ve boxed them up for now because it stresses me out to look at them. If someone had time and interest in swapping the switches for me, there might be a good parts radio in it for them. Just sayin’... On a different note, it seems that Es is starting to run. I tripped onto a small group of regulars on 27.425 AM early this morning. I don’t think they were aware the skip was rolling. Signals were 7 to 9+. I assumed that their signals were shifting polarization to horizontal, bringing my indoor horizontal wire dipole to life They could not hear me but it was nice to hear a group chatting on AM. First AM I’ve heard out here at all. Based on what they were talking about, I think they were in SoCal or western Arizona. The band was only open for about 10 minutes or so and then they faded away. Also built an experimental half-wave sleeved vertical dipole for the boat (encased in PVC to avoid shorts in the rigging) that can be hoisted about 30 feet above the water but need to strengthen it in the middle where it flexes before I can try it out and tune it. Hell man, vintage radios are supposed to alleviate stress not exacerbate it  . I'm glad you finally got to hear other stations out there, but it's sad that it takes a band opening to do it. I would think where you are, there would still be a following of radio ops. I know the old Tube Radio Net out in Fresno runs on channel 11 every Saturday night at 8:00 Pm PST. That might be a bit far from you (and on the other side of the mountain IIRC). But Dennis usually has a far number of check-ins. I can't believe it's that dead there. That would be more stressful for me than looking at radios in need of TLC..... I'd have to dig into old recordings or something.... |
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Post by whiskeycharlie242 on May 3, 2019 2:57:34 GMT -5
I’ve boxed them up for now because it stresses me out to look at them. If someone had time and interest in swapping the switches for me, there might be a good parts radio in it for them. Just sayin’... On a different note, it seems that Es is starting to run. I tripped onto a small group of regulars on 27.425 AM early this morning. I don’t think they were aware the skip was rolling. Signals were 7 to 9+. I assumed that their signals were shifting polarization to horizontal, bringing my indoor horizontal wire dipole to life They could not hear me but it was nice to hear a group chatting on AM. First AM I’ve heard out here at all. Based on what they were talking about, I think they were in SoCal or western Arizona. The band was only open for about 10 minutes or so and then they faded away. Also built an experimental half-wave sleeved vertical dipole for the boat (encased in PVC to avoid shorts in the rigging) that can be hoisted about 30 feet above the water but need to strengthen it in the middle where it flexes before I can try it out and tune it. Hell man, vintage radios are supposed to alleviate stress not exacerbate it . I'm glad you finally got to hear other stations out there, but it's sad that it takes a band opening to do it. I would think where you are, there would still be a following of radio ops. I know the old Tube Radio Net out in Fresno runs on channel 11 every Saturday night at 8:00 Pm PST. That might be a bit far from you (and on the other side of the mountain IIRC). But Dennis usually has a far number of check-ins. I can't believe it's that dead there. That would be more stressful for me than looking at radios in need of TLC..... I'd have to dig into old recordings or something.... There are some locals out here on 27.385 LSB but they’re not very active. Nothing on AM at all. With my antenna limitations I am too weak for most of them to hear, so not much fun. I also don’t hear them very well either, so I spend more time listening to my scanner, which is very active including 2M nets and even some locals running GMRS repeaters. Interestingly, local PD, fire and EMS is still analog without trunking so I hear everything. Not sure how much longer this will last as they finally have funding to go digital. Could take a few years to transition though. Fresno is a bit too far despite the quiet air waves. About 145 miles from me with a mountain range in between. The only way to hear this would be with a good mobile on top of Mt. Hamilton, which is 20 miles east of me and 4400’ ASL with a clear view to Fresno to the south. A nice export rig from there would probably make the trip. Hoping the boat will work out as it’s my best shot at a viable antenna system within an area that should have some activity. |
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Sandbagger
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Post by Sandbagger on May 4, 2019 13:06:22 GMT -5
Hell man, vintage radios are supposed to alleviate stress not exacerbate it . I'm glad you finally got to hear other stations out there, but it's sad that it takes a band opening to do it. I would think where you are, there would still be a following of radio ops. I know the old Tube Radio Net out in Fresno runs on channel 11 every Saturday night at 8:00 Pm PST. That might be a bit far from you (and on the other side of the mountain IIRC). But Dennis usually has a far number of check-ins. I can't believe it's that dead there. That would be more stressful for me than looking at radios in need of TLC..... I'd have to dig into old recordings or something.... There are some locals out here on 27.385 LSB but they’re not very active. Nothing on AM at all. With my antenna limitations I am too weak for most of them to hear, so not much fun. I also don’t hear them very well either, so I spend more time listening to my scanner, which is very active including 2M nets and even some locals running GMRS repeaters. Interestingly, local PD, fire and EMS is still analog without trunking so I hear everything. Not sure how much longer this will last as they finally have funding to go digital. Could take a few years to transition though. Fresno is a bit too far despite the quiet air waves. About 145 miles from me with a mountain range in between. The only way to hear this would be with a good mobile on top of Mt. Hamilton, which is 20 miles east of me and 4400’ ASL with a clear view to Fresno to the south. A nice export rig from there would probably make the trip. Hoping the boat will work out as it’s my best shot at a viable antenna system within an area that should have some activity. I can't wait to read the report on the boat antenna experiment. Hopefully you'll find something interesting out there that you can talk to. Otherwise, it might be time to invest some time putting together a mobile moutaintop setup. That way you'll be sure to find something from the top of a 5000' hill. |
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Post by whiskeycharlie242 on May 5, 2019 16:51:58 GMT -5
There are some locals out here on 27.385 LSB but they’re not very active. Nothing on AM at all. With my antenna limitations I am too weak for most of them to hear, so not much fun. I also don’t hear them very well either, so I spend more time listening to my scanner, which is very active including 2M nets and even some locals running GMRS repeaters. Interestingly, local PD, fire and EMS is still analog without trunking so I hear everything. Not sure how much longer this will last as they finally have funding to go digital. Could take a few years to transition though. Fresno is a bit too far despite the quiet air waves. About 145 miles from me with a mountain range in between. The only way to hear this would be with a good mobile on top of Mt. Hamilton, which is 20 miles east of me and 4400’ ASL with a clear view to Fresno to the south. A nice export rig from there would probably make the trip. Hoping the boat will work out as it’s my best shot at a viable antenna system within an area that should have some activity. I can't wait to read the report on the boat antenna experiment. Hopefully you'll find something interesting out there that you can talk to. Otherwise, it might be time to invest some time putting together a mobile moutaintop setup. That way you'll be sure to find something from the top of a 5000' hill. Well, the experiment was successful. I hoisted the antenna today to see if I could hear anything at all. I was surprised to hear a mobile on top of Mt. Diablo booming in so I gave it a shot. Made the contact on .385 LSB and had a nice QSO for a bit. That’s about 20 miles as the crow flies between a mobile at 4000 feet ASL to a marine portable at sea level. Signal report was about 5 S units. My modulation was a bit distorted so I suspect that high SWR was creating some issues that will clear up when I tune it and place my 1:1 balun inline to kill any stray RF coming down the coax. The only bad news is that there still seems to be little to no activity. But once I get things dialed in I’ll reassess. |
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Sandbagger
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Post by Sandbagger on May 5, 2019 21:24:18 GMT -5
I can't wait to read the report on the boat antenna experiment. Hopefully you'll find something interesting out there that you can talk to. Otherwise, it might be time to invest some time putting together a mobile moutaintop setup. That way you'll be sure to find something from the top of a 5000' hill. Well, the experiment was successful. I hoisted the antenna today to see if I could hear anything at all. I was surprised to hear a mobile on top of Mt. Diablo booming in so I gave it a shot. Made the contact on .385 LSB and had a nice QSO for a bit. That’s about 20 miles as the crow flies between a mobile at 4000 feet ASL to a marine portable at sea level. Signal report was about 5 S units. My modulation was a bit distorted so I suspect that high SWR was creating some issues that will clear up when I tune it and place my 1:1 balun inline to kill any stray RF coming down the coax. The only bad news is that there still seems to be little to no activity. But once I get things dialed in I’ll reassess. I guess I have to ask, how high was the SWR? If it was really high, it could cause distortion, as could RF feedback from the antenna being so close to the radio. Once you get thing squared away, it might be time to think about a small amp to give that all important 10db boost. It can make a difference when talking to more distant locals. It's much more comfortable listening to someone at an S7 level, than at S4 or 5, especially considering localized noise levels. |
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Post by whiskeycharlie242 on May 5, 2019 22:15:15 GMT -5
Well, the experiment was successful. I hoisted the antenna today to see if I could hear anything at all. I was surprised to hear a mobile on top of Mt. Diablo booming in so I gave it a shot. Made the contact on .385 LSB and had a nice QSO for a bit. That’s about 20 miles as the crow flies between a mobile at 4000 feet ASL to a marine portable at sea level. Signal report was about 5 S units. My modulation was a bit distorted so I suspect that high SWR was creating some issues that will clear up when I tune it and place my 1:1 balun inline to kill any stray RF coming down the coax. The only bad news is that there still seems to be little to no activity. But once I get things dialed in I’ll reassess. I guess I have to ask, how high was the SWR? If it was really high, it could cause distortion, as could RF feedback from the antenna being so close to the radio. Once you get thing squared away, it might be time to think about a small amp to give that all important 10db boost. It can make a difference when talking to more distant locals. It's much more comfortable listening to someone at an S7 level, than at S4 or 5, especially considering localized noise levels. The SWR was 3:1, so I’m not surprised by any of the symptoms. The next step is to tune it, which will be time consuming and best done on a windless day given that I gave to haul it down/up for each iteration. The distance to the radio shouldn’t be an issue. The feed point is about 25’ away. More important will be a good choke and RF ground, which I did not have in place for the first test. I may also do some re-engineering of the design for more structural rigidity and ease of tuning. I just wanted to see if it was operable at all before investing more time and money. It was apparent that the guy on top of the mountain was working a pile up of locals in all directions out to about 50 miles and also was working some DX from Texas and Montana that I couldn’t hear. The DX is starting to run out here, so I need to get going before the season escapes. |
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Sandbagger
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Post by Sandbagger on May 7, 2019 10:49:43 GMT -5
I guess I have to ask, how high was the SWR? If it was really high, it could cause distortion, as could RF feedback from the antenna being so close to the radio. Once you get thing squared away, it might be time to think about a small amp to give that all important 10db boost. It can make a difference when talking to more distant locals. It's much more comfortable listening to someone at an S7 level, than at S4 or 5, especially considering localized noise levels. The SWR was 3:1, so I’m not surprised by any of the symptoms. The next step is to tune it, which will be time consuming and best done on a windless day given that I gave to haul it down/up for each iteration. The distance to the radio shouldn’t be an issue. The feed point is about 25’ away. More important will be a good choke and RF ground, which I did not have in place for the first test. I may also do some re-engineering of the design for more structural rigidity and ease of tuning. I just wanted to see if it was operable at all before investing more time and money. It was apparent that the guy on top of the mountain was working a pile up of locals in all directions out to about 50 miles and also was working some DX from Texas and Montana that I couldn’t hear. The DX is starting to run out here, so I need to get going before the season escapes. Hopefully, you were able to determine, from taking SWR readings on your highest and lowest channels, which direction you need to go to tune. Hopefully they weren't all giving the same reading. That would indicate something other than simple tuning is causing the issue. And hopefully your best SWR was on your lowest channel. That would mean cutting it shorter to tune, which is a lot easier than having to lengthen.... Where's that old Trik-Stik when you need it........ |
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Post by whiskeycharlie242 on May 7, 2019 11:08:42 GMT -5
The SWR was 3:1, so I’m not surprised by any of the symptoms. The next step is to tune it, which will be time consuming and best done on a windless day given that I gave to haul it down/up for each iteration. The distance to the radio shouldn’t be an issue. The feed point is about 25’ away. More important will be a good choke and RF ground, which I did not have in place for the first test. I may also do some re-engineering of the design for more structural rigidity and ease of tuning. I just wanted to see if it was operable at all before investing more time and money. It was apparent that the guy on top of the mountain was working a pile up of locals in all directions out to about 50 miles and also was working some DX from Texas and Montana that I couldn’t hear. The DX is starting to run out here, so I need to get going before the season escapes. Hopefully, you were able to determine, from taking SWR readings on your highest and lowest channels, which direction you need to go to tune. Hopefully they weren't all giving the same reading. That would indicate something other than simple tuning is causing the issue. And hopefully your best SWR was on your lowest channel. That would mean cutting it shorter to tune, which is a lot easier than having to lengthen.... Where's that old Trik-Stik when you need it........ I think it’s more than simple tuning, which I’m well versed in having constructed and tuned several dipoles and mag loops recently. I think I may have a near field issue with the coax that could require a design change to sort out, but I need to remove some other variables first before concluding anything. I also found the length of it to be very cumbersome to work with on the boat. It can’t be installed permanently, so it needs to be easy to put up and take down. Even a Trik Stik wouldn’t be very practical for this, although it was a great antenna as you know. Surprised that MFJ doesn’t offer it anymore since they own Cushcraft. Stay tuned. Pun intended. :-) |
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Sandbagger
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Post by Sandbagger on May 7, 2019 20:54:02 GMT -5
Hopefully, you were able to determine, from taking SWR readings on your highest and lowest channels, which direction you need to go to tune. Hopefully they weren't all giving the same reading. That would indicate something other than simple tuning is causing the issue. And hopefully your best SWR was on your lowest channel. That would mean cutting it shorter to tune, which is a lot easier than having to lengthen.... Where's that old Trik-Stik when you need it........ I think it’s more than simple tuning, which I’m well versed in having constructed and tuned several dipoles and mag loops recently. I think I may have a near field issue with the coax that could require a design change to sort out, but I need to remove some other variables first before concluding anything. I also found the length of it to be very cumbersome to work with on the boat. It can’t be installed permanently, so it needs to be easy to put up and take down. Even a Trik Stik wouldn’t be very practical for this, although it was a great antenna as you know. Surprised that MFJ doesn’t offer it anymore since they own Cushcraft. Stay tuned. Pun intended. :-) I agree, there's metal within 1/4 wave of the antenna, and that will detune it. As can the feedline coming off of the center. Have you thought of trying a coaxial dipole design? Might be easier to deal with with the feedline at the bottom. I will certainly remained "tuned" Although I think I might be more reactive than resistive.......  |
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Post by whiskeycharlie242 on May 7, 2019 23:22:20 GMT -5
I think it’s more than simple tuning, which I’m well versed in having constructed and tuned several dipoles and mag loops recently. I think I may have a near field issue with the coax that could require a design change to sort out, but I need to remove some other variables first before concluding anything. I also found the length of it to be very cumbersome to work with on the boat. It can’t be installed permanently, so it needs to be easy to put up and take down. Even a Trik Stik wouldn’t be very practical for this, although it was a great antenna as you know. Surprised that MFJ doesn’t offer it anymore since they own Cushcraft. Stay tuned. Pun intended. :-) I agree, there's metal within 1/4 wave of the antenna, and that will detune it. As can the feedline coming off of the center. Have you thought of trying a coaxial dipole design? Might be easier to deal with with the feedline at the bottom. I will certainly remained "tuned" Although I think I might be more reactive than resistive....... Yes, there is a lot of metal within a 1/4 wave, but I think there are other issues to resolve first. A coaxial dipole is really just a sleeved dipole, which is essentially what I’ve built using flat copper plated steel pipe strap (for better skin effect without the weight of copper pipe or tube) encased in PVC. While the feed point is at the center, it consists of a half wave length of RG8X (adjusted for velocity) running parallel to the counterpoise inside the PVC, terminating with a PL259 exiting from the bottom of the counterpoise tube. The idea was to intentionally couple the feed line due to the near field placement and create a tripole. I decided to try to use the coax as part of the system rather than isolate it which would be very hard to do with a vertical dipole and the mounting constraints of the mast, boom and rigging. The first thing I will do is attach my inline balun to make sure that only the feedline coax radiates and not the run to the radio. Then I’ll try to tune it by trimming it since I designed it with extra length just for that purpose. I won’t get to this for at least a week or so, but will update you on progress or lack thereof then. 73 |
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Post by whiskeycharlie242 on Jun 2, 2019 19:30:50 GMT -5
I agree, there's metal within 1/4 wave of the antenna, and that will detune it. As can the feedline coming off of the center. Have you thought of trying a coaxial dipole design? Might be easier to deal with with the feedline at the bottom. I will certainly remained "tuned" Although I think I might be more reactive than resistive....... Yes, there is a lot of metal within a 1/4 wave, but I think there are other issues to resolve first. A coaxial dipole is really just a sleeved dipole, which is essentially what I’ve built using flat copper plated steel pipe strap (for better skin effect without the weight of copper pipe or tube) encased in PVC. While the feed point is at the center, it consists of a half wave length of RG8X (adjusted for velocity) running parallel to the counterpoise inside the PVC, terminating with a PL259 exiting from the bottom of the counterpoise tube. The idea was to intentionally couple the feed line due to the near field placement and create a tripole. I decided to try to use the coax as part of the system rather than isolate it which would be very hard to do with a vertical dipole and the mounting constraints of the mast, boom and rigging. The first thing I will do is attach my inline balun to make sure that only the feedline coax radiates and not the run to the radio. Then I’ll try to tune it by trimming it since I designed it with extra length just for that purpose. I won’t get to this for at least a week or so, but will update you on progress or lack thereof then. 73 I finally had the chance to get back to it today. The big issue has been sorted out - near field RF due to the design. I disassembled the antenna casing so I could get the coax out at a 90 degree angle. Then I was able to get the SWR into an operable range. Once I got it roughly tuned, the band was open so I gave it a shot and was surprised to work some Arizona stations on 38 LSB. Signal and audio reports were great. Also worked some locals but they were weaker than the DX stations. Not too shabby for a barefoot 40+ year old radio on a dipole at sea level. People were sure intrigued by my marine portable call. Now it’s time to reengineer the antenna system into something more robust. :-) |
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Post by Sandbagger on Jun 3, 2019 12:14:48 GMT -5
Yes, there is a lot of metal within a 1/4 wave, but I think there are other issues to resolve first. A coaxial dipole is really just a sleeved dipole, which is essentially what I’ve built using flat copper plated steel pipe strap (for better skin effect without the weight of copper pipe or tube) encased in PVC. While the feed point is at the center, it consists of a half wave length of RG8X (adjusted for velocity) running parallel to the counterpoise inside the PVC, terminating with a PL259 exiting from the bottom of the counterpoise tube. The idea was to intentionally couple the feed line due to the near field placement and create a tripole. I decided to try to use the coax as part of the system rather than isolate it which would be very hard to do with a vertical dipole and the mounting constraints of the mast, boom and rigging. The first thing I will do is attach my inline balun to make sure that only the feedline coax radiates and not the run to the radio. Then I’ll try to tune it by trimming it since I designed it with extra length just for that purpose. I won’t get to this for at least a week or so, but will update you on progress or lack thereof then. 73 I finally had the chance to get back to it today. The big issue has been sorted out - near field RF due to the design. I disassembled the antenna casing so I could get the coax out at a 90 degree angle. Then I was able to get the SWR into an operable range. Once I got it roughly tuned, the band was open so I gave it a shot and was surprised to work some Arizona stations on 38 LSB. Signal and audio reports were great. Also worked some locals but they were weaker than the DX stations. Not too shabby for a barefoot 40+ year old radio on a dipole at sea level. People were sure intrigued by my marine portable call. Now it’s time to reengineer the antenna system into something more robust. :-) If you can get SWR under 2:1, you should be in good shape. It'll make the radio happier, and clean up those distortions. Might be time to think about a small amp....... |
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Post by whiskeycharlie242 on Jun 5, 2019 18:42:50 GMT -5
I finally had the chance to get back to it today. The big issue has been sorted out - near field RF due to the design. I disassembled the antenna casing so I could get the coax out at a 90 degree angle. Then I was able to get the SWR into an operable range. Once I got it roughly tuned, the band was open so I gave it a shot and was surprised to work some Arizona stations on 38 LSB. Signal and audio reports were great. Also worked some locals but they were weaker than the DX stations. Not too shabby for a barefoot 40+ year old radio on a dipole at sea level. People were sure intrigued by my marine portable call. Now it’s time to reengineer the antenna system into something more robust. :-) If you can get SWR under 2:1, you should be in good shape. It'll make the radio happier, and clean up those distortions. Might be time to think about a small amp....... I took an alternate route and constructed a vertical wire dipole as it is a lot easier to deal with putting up/down. SWR is finally decent (1.8 to 1.3) across the band and the radio is much happier, as am I. With some more work I’ll get it down lower still. Have found some locals on 38 LSB around the bay to chat with and I’m getting out pretty well. Since there aren’t that many CBers around here, the new guy in the boat is getting a lot of attention. :-) The skip was rolling today a bit from the north, but hard for me to pick out stations due to my sea level elevation and lots of metal around me from all the sailboats. But I did make a nice 900 mike shot to NW Montana by the Canadian border. Things are looking up. More antenna experiments to come until I find just the right solution. I’m thinking about a J Pole that I can hoist above the top of the mast as a possibility but it would have to be a modular design that can be assembled in pieces from smaller elements. This might be a long term project. ;-) |
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Sandbagger
Administrator/The Boss
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Post by Sandbagger on Jun 5, 2019 18:59:52 GMT -5
If you can get SWR under 2:1, you should be in good shape. It'll make the radio happier, and clean up those distortions. Might be time to think about a small amp....... I took an alternate route and constructed a vertical wire dipole as it is a lot easier to deal with putting up/down. SWR is finally decent (1.8 to 1.3) across the band and the radio is much happier, as am I. With some more work I’ll get it down lower still. Have found some locals on 38 LSB around the bay to chat with and I’m getting out pretty well. Since there aren’t that many CBers around here, the new guy in the boat is getting a lot of attention. :-) The skip was rolling today a bit from the north, but hard for me to pick out stations due to my sea level elevation and lots of metal around me from all the sailboats. But I did make a nice 900 mike shot to NW Montana by the Canadian border. Things are looking up. More antenna experiments to come until I find just the right solution. I’m thinking about a J Pole that I can hoist above the top of the mast as a possibility but it would have to be a modular design that can be assembled in pieces from smaller elements. This might be a long term project. ;-) At least you're experimenting. That was always (more than) half the fun for me. |
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Post by cbrown on Jun 12, 2019 12:30:56 GMT -5
I agree, experimenting is what keeps the hobby fun.
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Post by bobcat4109 on Jun 12, 2019 13:32:51 GMT -5
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Post by whiskeycharlie242 on Jun 12, 2019 23:01:05 GMT -5
Interesting project, but not really practical for my application. I could make a J Pole using insulated wire and a piece of twin lead and hang it vertically from a “tree,” which in my case would the main halyard of my boat. The only problem this solves for me is that the antenna is now end fed, making it easier to run coax to the radio than at a 90 degree angle from a center fed dipole hanging high in the air. There are two other designs that I’m exploring as alternatives to the wire dipole I’ve already built, which is working pretty well at this point. One is what you might call a no ground plane antenna, but more correctly is a “resonant feedline dipole.” This would be more or less like a Shakespeare Big Stick marine CB antenna but suspended in free air vs. mounted to the boat. The radiator would be made of copper plated steel strapping inside a PVC tube (for insulation) with a 1/4 wave length of coax attached as a feedline with its shield ungrounded and a choke balun at the bottom. The resulting common current on the open coax shield becomes the counterpoise. The advantage here is less weight and being end fed. Performance should be the same as a wire dipole although it might work better due to increased skin effect of the flat strapping and the coax shield’s larger surface areas. The other is a coaxial double bazooka, which is similar to a center fed wire dipole but with the advantage of much lower noise and wider bandwidth. There is one commercially available that sounds like it would work very well for me and cost less than making my own. I’m pretty sure this one will end up being the best performer and easiest to deal with overall. I’ll let you all know what happens in a few weeks when I get it all together. |
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Post by whiskeycharlie242 on Aug 15, 2019 0:22:52 GMT -5
I’ll let you all know what happens in a few weeks when I get it all together. I promised an update in a few weeks. A lot has happened since my last post, some good, some not so good. The good part is that I have finally sorted out the antenna system. I ended up using a commercial double bazooka coaxial dipole from Radiowavz. It was much less sensitive to near field metal than my wire dipole, allowing me to raise it much higher and closer to the mast and with a flat match on 38, where I hang out. The antenna can be put up or taken down in a few minutes and coils up when I need to stow it. Not as convenient as a permanent mount antenna but I will get there eventually. The bad part is the very high noise level that makes it hard to hear well. After considering the possible sources and doing some research on nearby transmitters and DFing local RFI emitters around the dock, I’ve decided to try active noise cancellation as passive filters and DSP don’t help much. I have an MFJ 1026 on the way and will use my half wave no ground plane stick for a noise antenna. The boat is starting to look like an antenna farm but once everything is sorted then I’ll engineer a more elegant and more permanent installation. I’ve also picked up my tech ticket and some dual band HTs to play with, but honestly, it’s not as much fun as CB. FM mode, repeaters, the internet and a bunch of stuffy old hams is pretty dull and nothing compared to working DX on SSB on a classic CB. We have a ham flea market out here once a month that’s been going on for 35 years. I had no idea all these years since it starts before dawn and it is unadvertised. People show up with flashlights to snap up the best deals before many sellers have even arrived. It’s quite the show. I’ve scored a few classic CBs there for cheap including one rare one that I’ll let Sandbagger tell you about. I’ll update again once I’ve tried the noise eliminator out. |
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Post by TheStonerGuy on Jan 18, 2020 10:45:12 GMT -5
I'll bite.... any update(s)? 
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Post by whiskeycharlie242 on Jan 18, 2020 12:05:24 GMT -5
I'll bite.... any update(s)?
Well, since you asked... The MFJ noise eliminator actually works pretty much as advertised, but it requires experimentation and finesse to get great results. To work best, the noise antenna needs to be optimized for receiving the noise you want to eliminate but not the signals you want to keep. Since most QRM is vertically polarized, a vertical antenna is recommended. As the noise antenna is not a transmit antenna, it doesn’t have to be precisely tuned or even have a usable SWR. I started off using a homemade 1/4 wave vertical roughly tuned for 11m and it worked well enough to knock certain types of noise down 2 S-units or more, but I wasn’t satisfied with it. It still received too much desired signal and was taking some of that down as well. Using an HF rig to determine where my noise was highest, I then built an antenna for that band but it was too good and actually introduced more noise than it eliminated. So, my next planned experiment was to make an antenna that was just far enough away from 11m that it attenuated the desired signal but still strongly received the noise I wanted to eliminate. I thought that would work best, but since I’m moving to a new QTH I will need to start over as I don’t know if I’ll have a QRM problem there or not. I can recommend the MFJ 1026 but it requires a certain level of knowledge about its design and an experimental approach to make it work for your situation. If that’s not really your thing, then you probably won’t be satisfied. FWIW, I think some of the negative reviews I’ve seen are a reflection of the user’s lack of knowledge and experimentation more than a deficiency of the product. |
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Post by bobcat4109 on Jan 18, 2020 13:05:07 GMT -5
I’ve also picked up my tech ticket and some dual band HTs to play with, but honestly, it’s not as much fun as CB. FM mode, repeaters, the internet and a bunch of stuffy old hams is pretty dull and nothing compared to working DX on SSB on a classic CB. WhiskeyCharlie242, Not that you needed the help but I just really wanted to chime in on this point. My son Tim and I have been in CB off and on for a while, and have both found our way to a tech ticket and 2m/70cm radio. Yes, we enjoy the clarity of repeaters and FM. That said........ it is just..."different". I still have a strong "calling" to the informal, rogue, "wild in the bush" trappings of CB radio. Tim is beginning a trek to the HF side of ham. As he is meeting more hams (AND I might add.... doing a lot of good volunteering time to help older hams who can't mess with antennas or even reconfigure their benches/desks well) ..he is also finding deals on HF equipment that he has set up for listening ONLY. He only has a tech ticket and he is a VERY conscious type about NOT operating on bands without the right license! But his appetite is getting SO WHET for getting his general ticket that he can't stand it. I have listened in to some on his radio...and some on websdr.org.... but still it is just..... different!!!!! CB just..... "speaks to me"! Good luck in your adventures. THIS is the stuff that makes this hobby great! |
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Post by whiskeycharlie242 on Jan 18, 2020 13:43:36 GMT -5
I’ve also picked up my tech ticket and some dual band HTs to play with, but honestly, it’s not as much fun as CB. FM mode, repeaters, the internet and a bunch of stuffy old hams is pretty dull and nothing compared to working DX on SSB on a classic CB. WhiskeyCharlie242, That said........ it is just..."different". I still have a strong "calling" to the informal, rogue, "wild in the bush" trappings of CB radio. CB just..... "speaks to me"! Good luck in your adventures. THIS is the stuff that makes this hobby great! Hey Bobcat, Thanks! I agree completely. The ham experience is just different and doesn’t compare to the character of CB in most ways. I simply enjoy the people I meet and talk with more. For example, this morning I worked a station in Australia on 2M via the WIN System using my Baofeng HT with a rubber duck antenna. While I enjoyed talking to the guy (a firefighter actually) there was no sense of accomplishment in it. I did nothing other than buy a $25 radio and key it up, more or less. To do the same on CB would require a combination of technologies, knowledge and mastery of each along with the right conditions. When it all comes together like that it is exciting and memorable. Do you remember the feeling you had when you made your first ever DX contact? Or the delight when the response to a break from you came from someone hundreds or thousands of miles away when you were expecting it to be from someone a few miles away? While you can have a similar experience on HF the feeling just isn’t the same unless you build your own equipment or antennas. The off the shelf stuff is just so good that practically anyone can work DX easily and reliably when the bands are open. Lately, the most fun I’ve had is engineering my way from being a mud duck that the locals could barely hear to being a station they admired to the point of creating something of a guru reputation around the area. I hope your son sticks with it for life. We need the next generation to embrace radio in all forms lest it become extinct. You’ve apparently had a real influence on him. It must be very satisfying to see him pick up the torch and carry on. Regards, Mitch |
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Sandbagger
Administrator/The Boss
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Post by Sandbagger on Jan 18, 2020 17:21:27 GMT -5
WhiskeyCharlie242, That said........ it is just..."different". I still have a strong "calling" to the informal, rogue, "wild in the bush" trappings of CB radio. CB just..... "speaks to me"! Good luck in your adventures. THIS is the stuff that makes this hobby great! Hey Bobcat, Thanks! I agree completely. The ham experience is just different and doesn’t compare to the character of CB in most ways. I simply enjoy the people I meet and talk with more. For example, this morning I worked a station in Australia on 2M via the WIN System using my Baofeng HT with a rubber duck antenna. While I enjoyed talking to the guy (a firefighter actually) there was no sense of accomplishment in it. I did nothing other than buy a $25 radio and key it up, more or less. To do the same on CB would require a combination of technologies, knowledge and mastery of each along with the right conditions. When it all comes together like that it is exciting and memorable. Do you remember the feeling you had when you made your first ever DX contact? Or the delight when the response to a break from you came from someone hundreds or thousands of miles away when you were expecting it to be from someone a few miles away? While you can have a similar experience on HF the feeling just isn’t the same unless you build your own equipment or antennas. The off the shelf stuff is just so good that practically anyone can work DX easily and reliably when the bands are open. Lately, the most fun I’ve had is engineering my way from being a mud duck that the locals could barely hear to being a station they admired to the point of creating something of a guru reputation around the area. I hope your son sticks with it for life. We need the next generation to embrace radio in all forms lest it become extinct. You’ve apparently had a real influence on him. It must be very satisfying to see him pick up the torch and carry on. Regards, Mitch Ham radio has far more capability, and way more diversity in the technologies and methods to communicate. But somehow, it seems dry and lacking in that "down home" feeling that CB radio gives you. I think part of it is that for older operators like us, who discovered the magic of radio at a young age via CB during the heyday of the hobby, we are looking to recapture those feelings that we had back then. It's what drives us to collect vintage radios and drawing us to scanning the channels looking for other people to talk to. Ham radio just doesn't have that same connection. But that also depends on the local operators. 2 meters can be fun if there's a good crew. We had a local group of mostly ex-CB'ers who talked on Simplex, in much the same way as we would have on CB. The characteristics of FM and VHF made for some better local coverage, and cleaner audio quality. But still, it's not the same. Maybe if I transplant a 2 meter radio into an old CB cabinet.......... Nah..... |
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Post by TheStonerGuy on Jan 19, 2020 19:21:23 GMT -5
I'll bite.... any update(s)?
Well, since you asked... The MFJ noise eliminator actually works pretty much as advertised, but it requires experimentation and finesse to get great results. To work best, the noise antenna needs to be optimized for receiving the noise you want to eliminate but not the signals you want to keep. Since most QRM is vertically polarized, a vertical antenna is recommended. FWIW, I think some of the negative reviews I’ve seen are a reflection of the user’s lack of knowledge and experimentation more than a deficiency of the product. Thanks for the update. I happened across the original post and kept reading, but when it just stopped it was like someone taking a book out of hands before I could finish reading it
Re: HAM radio and/or CB radio posts
The most thrilling Dx I ever made was with a stock SSB CB radio. I got my ticket years ago but didn't warm up to repeater life, ran into the usual Hams hate CBers thing, but I do plug away on other HF bands when 11m is dead. I'm almost always QRP, and I found I can still get a kick out of making a contact (anywhere) on 5-10 watts. 
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