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Post by SteveInOregon on Feb 16, 2011 2:44:46 GMT -5
Hello,
I don't know if this question is apropos but here it goes.
I have a vintage collectible Stoner Pro 40 SSB made in 1978.
It works just fine except for one big issue, when I TX for a long time perhaps a 45 sec to one minuet with no let up it will suddenly almost go completely dead, this happens only during TX and only when I am keying up for a long period of time, the freq counter display dies, the meters no longer work ( the meter light still stay on ) and TX goes out ( no modulation / no signal out ) the unit is not completely black and off / dead , but mostly dead. and will stay in a state of half dead untill I shut off then turn back on and then all is well.
If I turn it off / and then back on I can start again and only when I key up and speak for more than just a few seconds, then it will die off again.
The lights , modulation, outgoing signal, clarity etc.... all do not go down slowly, rather this is a fast oncoming "lights out" type of sudden yet predictable issue.
My SWR antenna match if flat and tested, and I even switched to a few other radios to check and my antenna system is fine, I have wiggled the AC cord and it is solid, the little glass "fast blow" type fuse dis not / does not blow out, my power is 120V AC which is running my Astron power supply to my Kenwood 430 with no problems. This unit is 2nd hand, there is no burning smell from it, it is "warm" when used in TX and keyed for how ever long it takes to "kill the power" .
I can leave it on in receive all and and all night with no problem !
I expect "issues" with any old peace of gear like this, so this is not frustrating , rather is it fun to learn to diagnose as i am new to the inside of radio gear, so I am just trying to be led in the right direction
I know this is a broad generalized question about a pretty rare CB so I don't expect much, I do have the manual / schematic so perhaps there is a hint in what I am saying,a clue, perhaps a basic set of probable causes that You may lead me to check.
My amateur radio tech & pro TV & PC repairman wizard friend will be by to take a look later on this week and I would like to see if I can help him and myself to start in the right direction.
Any ideas ?
PS: If we get stumped and cannot fix it, then is there a qualified professional radio tech who can go through it and not only fix this big issue but go through it completely as a rig like this deserves to be put into tip top shape as I intend to keep it until I croak and my radio tech buddy will get it in my will, lol.
regards Steve KF7ARG
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Sandbagger
Administrator/The Boss
Posts: 6,250
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Post by Sandbagger on Feb 16, 2011 8:02:24 GMT -5
Hello, I don't know if this question is apropos but here it goes. I have a vintage collectible Stoner Pro 40 SSB made in 1978. It works just fine except for one big issue, when I TX for a long time perhaps a 45 sec to one minuet with no let up it will suddenly almost go completely dead, this happens only during TX and only when I am keying up for a long period of time, the freq counter display dies, the meters no longer work ( the meter light still stay on ) and TX goes out ( no modulation / no signal out ) the unit is not completely black and off / dead , but mostly dead. and will stay in a state of half dead untill I shut off then turn back on and then all is well. If I turn it off / and then back on I can start again and only when I key up and speak for more than just a few seconds, then it will die off again. The lights , modulation, outgoing signal, clarity etc.... all do not go down slowly, rather this is a fast oncoming "lights out" type of sudden yet predictable issue. My SWR antenna match if flat and tested, and I even switched to a few other radios to check and my antenna system is fine, I have wiggled the AC cord and it is solid, the little glass "fast blow" type fuse dis not / does not blow out, my power is 120V AC which is running my Astron power supply to my Kenwood 430 with no problems. This unit is 2nd hand, there is no burning smell from it, it is "warm" when used in TX and keyed for how ever long it takes to "kill the power" . I can leave it on in receive all and and all night with no problem ! I expect "issues" with any old peace of gear like this, so this is not frustrating , rather is it fun to learn to diagnose as i am new to the inside of radio gear, so I am just trying to be led in the right direction I know this is a broad generalized question about a pretty rare CB so I don't expect much, I do have the manual / schematic so perhaps there is a hint in what I am saying,a clue, perhaps a basic set of probable causes that You may lead me to check. My amateur radio tech & pro TV & PC repairman wizard friend will be by to take a look later on this week and I would like to see if I can help him and myself to start in the right direction. Any ideas ? PS: If we get stumped and cannot fix it, then is there a qualified professional radio tech who can go through it and not only fix this big issue but go through it completely as a rig like this deserves to be put into tip top shape as I intend to keep it until I croak and my radio tech buddy will get it in my will, lol. regards Steve KF7ARG My first thought is that there is a voltage regulator shutting down. I'm not sure if it's due to an overload, or just that the regulator part itself is bad. But when you check the radio out, pay particular attention to supply voltages inside the radio. I would be willing to bet one of them drops out.
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Post by cbrown on Feb 16, 2011 10:35:57 GMT -5
I agree, especially since it's happening only on transmit and the unit can stay on receive without any problems.
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Post by rifleman on Feb 16, 2011 12:50:04 GMT -5
Hi Steve, GREAT RADIO !!
Good thing you have the manual with it.
I would FIRST do a check on the power supply. A good thing to do with any "NEW" 30+ year old radio. LOL !!
There are 5 LEDs on the boards that by when they are lit, give you info on the power supply voltages. Give several good read-throughs on the manual, especialy the test procedures for the power supply, and the PLL/Counter board. Take the covers off, operate the rig untill it stops, and check out the LEDs again to determine which, if any, voltage is going out.
After that, I would look at the VCO going out-of-lock. On that radio, when the VCO goes out-of-lock, it PARTIALY disables the display, transmitter, and receiver.
Good luck, they are great radios. Very well designed and built. Once you get used to them they are simple to test and repair.
Yours, Ron
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Post by SteveInOregon on Feb 16, 2011 16:15:58 GMT -5
Thanks guy's for replying .
Well the 1st hour I was using it I was VERY impressed with a few things.
1) The adjacent channel / bleed over / interference rejection was PHENOMENAL, I have it on a three position coax switch, joined to my RoadTalker, I switched to the my mint and peaked Road Talker sitting next to the Stoner, I put the Road Talker on 38AM and listened to the Stoner on 38 LSB with the Stoner on open squelch and I head barely the slightest little scratch and blip of the S meter and only on the peaks getting past the Stoner to my ears !!! and that is on the same freq & my antenna is only 30 ft above the radios !!! if I take the rubber duck antenna off my Cheeroke SSB HT and key up on AM while my Road Talker is on SB it will want to jump out of my hand with bleed over blow out front end mod, but not the Stoner.
I also left it on all day and night switched to my Imax 2000 and on my 35 ft building the antenna is another 30 ft so that is 65ft up , but dig this my building is only 50 yards away from a major freeway , I can literally throw a baseball to the interstate 5 fwy, and so on ANY other radio I own such as my Kenwood TS-430-S, RoadTalker, Browning Baron , Palomar 2900, UnidenPC 122 or RCI 2950 with Shotkey Diode receive noise mod, on any of these radios the truckers on AM CH 15 and me on 38 LSB they litteraly blow me away with S9 bleed over, but ZERO bleed over gets past the Stoner , I mean ZER0, even with squelch wide open.
2) The noise suppression / noise blanking / quieting is also PHENOMENAL , it is as good as a brand new high end Kenwood.
I am located in a commercial building, surrounded with an RF field of florescent lights, steel tower high tension power lines and a power transformer station only 100 yards away.
The lowest S units of "hash" I get is 3 with an average of 5 and it is quite normal to have 6 raw units of sizzling mind blowing bacon frying hash, but ZERO with the Stoner !!!
When I 1st head the quiet RX of the Stoner I thought my coax was shorted out, but no it was not, and then I thought, man o man this Stoner is dead, but no because all of a sudden my friend 5 miles away keyed up and scared the crap out of me as he was so strong and clear as he always is but the comparison of signal to noise was so good it startled me, lol.
This is the same thing I get when I drive out into the county were my CB has no hash interference and so I can leave the squelch open all the time, and You wont know if the radio is on onky if you look at it to see the lights are on, the Stoner can do that down town in the big city.
3) The audio on RX / receive is superior, it does not matter if it is a tiny 8ohm lap top computer speaker or a 8 ohm big home stereo studio monitor the Stoner sound is real nice when listening, this along with the "Null" , the "Peak" and "Whistle Stop" tune options I can tailor the audio RX to one particular station like only that found on an HF Ham radio like my Kenwood.
4 ) The audio reports of my TX from my friends on 38LSB, seven of us in all, all of them say " Nice" "Sweet" "Clear" "Clean" etc......and all manner of Pos+ comments and this with only a cheep Radio Shack Chinese un-amplified mic, as the Stoner has a pre amp/ compression unit with manual switch built in.
My friends say it is almost as good as my Icom SM-10 three way graphic equalizer - pre amplified compressor mic.
So the power cut off is just a small road block.
I will post some photos in my next posting, and make a video of this fine old SB unit as the videos on YouTube seem to be just "look at my toys" type of videos rather than being an evaluation of a collectible, they dont show the features, they also don't show the inside of the radio for other folks who are thinking on buying one or fixing one.
(( There is one on E-bay right now "winks" ))
PS: I have a Tram D201A and a couple CPI's coming so I will do a "shoot out" once they are all set to factory specs as best my tech buddy and I can do and give an honest evaluation as to what their pos+ & -neg's are and are they really that much better other radios, and are they worth buying to use over just collecting them as shelf trophies, and if then for how much.
Right now without knowing if the Stoner is truly aligned, to factory spec, to it's full potential my Road Talker has "better" ears, much noisier and better S unit receive. I can hear my far off friend 40+ miles away over hills and thru valleys better by 2 S units on my Road Talker than the Stoner.
Stay tuned this should be fun.
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Post by rifleman on Feb 16, 2011 16:40:37 GMT -5
Get yourself some non-amplified D104's ("G" stands) (You will need one anyway for the Tram). That is what both the Stoner AND the D201A came with from the factory.
WOW !! What A Setup... You will have everyone in your area drooling !!!
Run the D201A through the Stoner for your AM work... Man will you be 10-8 on BOTH AM and SSB !!! (You WILL need a big desk though.. LOL !!!)
To me, the only things that will be missing from your "Super Collection" is a Sonar FS-2340 with a Demco mic modulator, and an ARF 2001 !!!
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Post by SteveInOregon on Feb 16, 2011 19:28:49 GMT -5
Hi, The Tram comes with a D104 wired for it.
The CPI base and CPI mobile's ( 2 of them ) with all the add on's etc...etc... are all rig's that I could NEVER afford as a teen or as a young man or as a married guy, lol, but now that I am single and so I can afford to start collecting, so what the heck, why not, it's not like they loose value, if they are in tip top shape in every way, ( they will be after I am done with them ) then they are just another way to save money and have fun at the same time.
Speaking of D104, did have a lollipop back in the 80's on my 1st SSB'er a RoadTalker and I really liked it, I set it on the floor and keyed it up like a gas peddle with my foot, i had an old Palomar 300A and I use to watch the tubes flicker purple-blue and talk to Hawaii al the time from San Diego, lol.
By the way Stoner is a side band only rig, yes Stoner made an AM add on box / accessory that could be wired in series with a coax jumper to keep the AM'er in you happy, but that is strictly an after thought for Don Stoner , and so good luck finding a single ad on for a Stoner, besides I am a SideBand'er all the way, but I would kill to have the HF 10-20-40-80 meters upgrade box Stoner made, but again good luck finding one of those
Funny You mentioned ARF -2001, I just passed one up as I was in between pay checks and bills bla bla bla, lol.
Here is another one of those "fish stories" > I really do know were there is a CPI base new un-used , still in the original box !!! "evil grinz".
Have You seen TramDr, ( he is on YouTube ) he is a nice guy, I think he is in Detroit MI , I think I even heard him on the boo-coo skip thee other day as # 257, any way's he has all the radios I have anda lot more MORE because he likes AM boxes, he has a clean Demco modulator, a "see thru" demonstrator , ultra rare ARF, and the *Motorola 40CH SSB that *I want to acquire.
You know I live in an RV and keep my radios at my work, when I move offices from this large room I use, I will have to sleep with my gear in an RV, so I better start collecting tube radios because transistor gear won't keep me warm in my cramped RV, LOL. I have already designed in my imagination a way of taking the fold down spare sleeper bunk in the front of my RV and making it into a CB Ham radio shelf to hold all this stuff, lol
UPDATE: The Stoner has been on all day, it "hiccuped" while sitting idle in RX twice, both times it was so fast I hardly noticed it except it did turn on and off how do I know, because the channel / freq readout went back to CH 9, You see when you turn the unit on it starts on CH 9 , and it went to CH 9 twice today, so off with the cover tonight to probe around after the good advice You guys gave me.
Thanks again guy's Stoner 396
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Post by rifleman on Feb 16, 2011 20:26:58 GMT -5
Good stuff Steve.... But does'nt your radio have the AM switch on the front, like this ? Attachments:
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Post by rifleman on Feb 16, 2011 20:32:41 GMT -5
... or these 2 SO connectors on the back ?? Attachments:
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Post by SteveInOregon on Feb 16, 2011 21:34:36 GMT -5
Good stuff Steve.... But does'nt your radio have the AM switch on the front, like this ? Yup, it sure does. Say , do You have an original manual , as all I have is a fuzzy copy taken off the internet that is hard to see ??
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Post by rifleman on Feb 16, 2011 21:42:26 GMT -5
Well you can run an AM radio through the Stoner, utilizing the Stoner's frequency counter and its TVI filter. The accessory box you are talking about is for powering a 12 volt radio through the Stoner's front panel. But you can run a Base unit alongside the Stoner. The original PRINTED copys of the manuals I had, I sold with the Stoners. Here is a copy of the manual. It is pretty clear, though the schematic is a little fuzzy, but readable. Attachments:
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Post by SteveInOregon on Feb 17, 2011 11:14:25 GMT -5
Thanks for the help.
The AM coupling to the Stoner is very creative yet useless to me as I am a pure SB man.
Upon further inspection the 2 final transistors ( what I think are finals ) which are screwed down to a large bulkhead used as a heat sink ,, each via a single screw set thru them , look to be replacements as the board were one attaches is "darkened" as if there was an SWR over heating / meltdown. The solder has blobs & gobs un-professionally melted onto the transistor connection to the board as if a shade tree / wannabee tech with a RadioShack solder pen got in there.
There is what I call a "buss" a 2in long by 4mm wide plastic multi pin connector behind the radio face that ties the face to the board via a dozen small pin / legs and that looks to have had been re-soldered by the same amateur as the plastic is melted probably because the solder pen tip was the wrong size or wrong heat range.
Please allow me to rant a bit, because I am still PISSED OFF about what I just found, as someone down the line drilled multiple holes in the bottom cover for a PC fan and more holes in the back cover for "ventilation" !!!! This is a high end CB , not an off the shelf RadioShack Nava-Ho, lol. Can You believe that,
Funny thing about working on radios, I would like to replace finals, diagnose myself bla bla bla, it is mildly interesting to me because I like to have a basic knowledge of what is under the hood, I'm a man and so I like engineering, tech and mechanical it's in our blood, ah "but" I would NEVER start in on a collectible radio like this until I worked my skill level up to a high degree in both diagnostics and the physical act of soldering for pete sake, and having the right equipment to lay down a bead.
This kind of monkey brain home made fix it jive is not found only in blue collar CB land, no it is a virus that spreads into all of radio land, lol. I know of plenty of pseudo intellectual Ham's who have jittering unsteady hands , old cataract eyes, a whole LOT of money, a lot of time, and a some ARRL book learning and they open up high end HF gear and glob solder and yank transistors till the radio is worse then when they started.
I digress; Pictures and Video coming.
PS: The on line PDF manual schematic realy is "fuzzy" to an extreme, the last page is almost useless as far as numbers and letters go, but my tech friend thinks he can tackle the basics.
Thanks again.
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Post by cbrown on Feb 17, 2011 11:20:08 GMT -5
That your Stoner on Ebay?
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Post by rifleman on Feb 17, 2011 14:22:42 GMT -5
Not mine on Ebay...... Steve, sorry to hear that it has been "Butcherd".... Both of mine had gotten the "Golden Screwdriver" treatment before I got them also, and had to be straightened out. The Stoner DOES NOT have a SWR protection circuit in them, so you can blow the finals in them with a bad antenna setup. BUT there is NO REASON why someone would put a cooling fan on one except if there was a ongoing problem. It could be that someone put higher wattage finals in it, and needed a fan to keep them cool. OR, what I think is someone blew the finals in it, and did not know how to mount the replacements correctly to the Heat Sink" bulkhead" and they kept on overheating and failing. One that I received had heat sink compuond smeared all over the inside of the radio !! Even if the board traces at the finals are burned away, it is worth having someone repair them. One of the Stoners I had was a rare older one that had a factory installed speaker in the bottom (some of the early ones had them). Good luck !!! Attachments:
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Post by SteveInOregon on Feb 17, 2011 19:33:20 GMT -5
OHhhhhhhh ok, so the same guy who messed with my Stoner messed with both of your Stoner's, lol, this guy sure get's around, lol.
Update: My radio tech buddy and I have been into the Stoner for the last few hours.
Without having any bottom side schematic , no schematic available for that side is a serious road block.
We have noticed that the finals are not original , the board is seriously discolored probably from burned out original finals.
The replacement finals in it now are one Motorola MRF475 & a Motorola MRF476 whether the radio is capable of higher wattage than 12 is sorta mute, as I think I remember Mr Stoner stating very plainly to NEVER drive the Pro40 past it;s original clean wattage ( paraphrased ).
We also noticed what is a 8715 voltage reg under a removable 1x1inch C shaped overhead heat sink soldered into a small 4x4 PCB board located right behind the front face plate AC-Power switch which has overheated & scorched the board but the board is still ok.
Mt tech buddy is going back to his place for a replacement regulator
We found 3 bad Cap's & replaced them all.
So stay tuned, once we get it back up and running we will try to give it better ears, because right now my RoadTalker has 3 S unit receive over the Stoner, but that is a fully aligned R T and the Stoner is, well who the hell know how whacked out the Stoner is.
Stay tuned & join us in our next edition of: a Stoner once owned by a stoned bone head stoner
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Post by SteveInOregon on Feb 17, 2011 20:19:25 GMT -5
That your Stoner on Ebay? No Sir, not mine
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Post by rifleman on Feb 17, 2011 21:46:19 GMT -5
I like that... a "stoned bone head Stoner owner" !! LOL !! For your info, the mods for extra upper freq. and the clarifier are very simple, and are in CB Secrets Volume 4 pgs. 52 & 53. (See how the display shows "HI" when the freq. mod is on) The freq. mod calls for using a shorted plug to be inserted into the headphone jack. One radio i had used a black on/off push button in place of the headphone jack. Very clean and stock looking. (See Photo) Greg Barkett at Barkett Electronics used to sell a manual for the PRO-40 (I had one) that has all of the views and schematics, PLUS the mod info in it. If you need it, you should contact him. He is an excellent person to deal with. PS... if you go down near the bottom of this web page, it has some of the schematics that are missing from the on-line version of the manual. www.sofafunker.de/stoner/stoner.htmAttachments:
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Post by SteveInOregon on Feb 18, 2011 0:42:33 GMT -5
I like that... a "stoned bone head Stoner owner" !! LOL !! For your info, the mods for extra upper freq. and the clarifier are very simple, and are in CB Secrets Volume 4 pgs. 52 & 53. (See how the display shows "HI" when the freq. mod is on) The freq. mod calls for using a shorted plug to be inserted into the headphone jack. One radio i had used a black on/off push button in place of the headphone jack. Very clean and stock looking. (See Photo) Greg Barkett at Barkett Electronics used to sell a manual for the PRO-40 (I had one) that has all of the views and schematics, PLUS the mod info in it. If you need it, you should contact him. He is an excellent person to deal with. PS... if you go down near the bottom of this web page, it has some of the schematics that are missing from the on-line version of the manual. www.sofafunker.de/stoner/stoner.htmTHANKS RifleMan You are saving us a huge headache . The older fellow I bought the Stoner from is actually a very nice guy , he did not do any of the butchering, in fact He is "giving" me a D201 for the hassle & headache over this. If I can get the photos to upload here I will share the diagnosis, perhaps this will be constructive and will help other future or present Stoner guy's. regards
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Post by cbrown on Feb 18, 2011 11:26:48 GMT -5
Interesting. I know Steve is a common name, but a Stoner isn't a common rig. I saw the person on Ebay selling the Stoner was named Steve, and I wondered.
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Post by rifleman on Feb 18, 2011 14:43:18 GMT -5
I used to monitor Ebay, and I would see the SAME radios being sold over and over.
Some CB'ers (and some Hams), that have no soldering skills whatsoever, cannot leave well enogh alone, and have butchered high-end radios all to heck.
Brownings, Trams, Stoners, 2000GTL's, and Siltronix's that have been screwed up, float around untill they finaly find a home with someone who can straighten them out.
The worst I have personaly seen are DAK X's....
I would have to say that at least 90% of them have PLL traces screwed up, have been rewired for bigger tubes, and holes drilled in their faces for more switches.
I have found that the hardest thing about straightening these radios out, is trying to figure out what has been done to them before !!
Thanks for letting me rant....
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Post by SteveInOregon on Feb 18, 2011 15:03:24 GMT -5
Interesting. I know Steve is a common name, but a Stoner isn't a common rig. I saw the person on Ebay selling the Stoner was named Steve, and I wondered. Ya that guy "Steve" ( not me ) who is selling the Stoner on Ebay he is in OK, I am in Oregon. Check this out, the older gentleman who sold me my Stoner is from OK, and he knows the Steve on E-bay who is selling the Stoner you are speaking about, they are not friends but he knows him.
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Post by SteveInOregon on Feb 18, 2011 20:43:26 GMT -5
I used to monitor Ebay, and I would see the SAME radios being sold over and over. Some CB'ers (and some Hams), that have no soldering skills whatsoever, cannot leave well enogh alone, and have butchered high-end radios all to heck. Brownings, Trams, Stoners, 2000GTL's, and Siltronix's that have been screwed up, float around untill they finaly find a home with someone who can straighten them out. The worst I have personaly seen are DAK X's.... I would have to say that at least 90% of them have PLL traces screwed up, have been rewired for bigger tubes, and holes drilled in their faces for more switches. I have found that the hardest thing about straightening these radios out, is trying to figure out what has been done to them before !! Thanks for letting me rant.... Your "rant" is well received, I agree 100% with You. So let me ask You, how do I upload photos to this thread, when I try it freezes up ? I did a search for photo upload and it was no help, as I want to show You folks and future Stoner peeps what to look for with this set of problems.
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Post by rifleman on Feb 18, 2011 21:00:29 GMT -5
I have just attached JPG files, and had no problems.
Maybe someone else here can answer that.....
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Post by SteveInOregon on Feb 19, 2011 1:20:37 GMT -5
I have just attached JPG files, and had no problems. Maybe someone else here can answer that..... My friend said to re-size them, so I am doing that and so I will post the photos of the Stoner problems as we found them ASAP.
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Post by SteveInOregon on Feb 19, 2011 17:17:54 GMT -5
Power supply board, bottom view . You see it turned over so You can see the traces and the glob of burned solder were the 3 pin voltage regulator plugs into this little board. This board is located directly behind the front face and has the push in buttons attached to it, the AC (power ), the MIC ( pre-amp ) and the AM ( option ) push in switch buttons. Attachments:
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Post by rifleman on Feb 19, 2011 18:04:37 GMT -5
That is the power supply board.... One of the large transistors is the 13.6 volt regulator (Q203), and the other is the 5 volt regulator (Q202). Both of the those transistors should be MJE3055's. If you don't have it, here is the schematic for it. Attachments:
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Post by SteveInOregon on Feb 19, 2011 19:47:53 GMT -5
THANK U ;D
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Post by SteveInOregon on Feb 19, 2011 19:57:01 GMT -5
This is the same board top side as seen when You look down into the top of the radio, obviously it is un-plugged from the multiple wire loom plugs. When it was in the radio, it was hidden under a three sided 1"x1"x1" gold colored C shaped heat sink type of hood so I had to get under it with a flash light to see the burned discoloration up and the ugly solder . If you look down to the lower right bottom of the board You will see the three push buttons attached to it that go thru the front radio face and stick out for the operator to use as described in photo #1. Look and You will see the top side of the burned out 3 leg / pin voltage regulator and the ugly blob of solder on it. Attachments:
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Post by SteveInOregon on Feb 19, 2011 20:07:08 GMT -5
This is a photo of the Stoner finals as seen looking directly down into the radio. You will see a seriously burned one on the left side , globs of shade tree mechanic solder and small associated components right next to it that got scorched, also the one on the left is not even screwed down all the way to the large bulkhead heat sink The one on the left is MRF 476 the one on the right is MRF 475 Question: Are these the final numbers called for from the factory ? We will replace them with original number finals or thier equivalent, we will replace the two voltage regulators and we have alread replace the bad cap's. Attachments:
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Post by SteveInOregon on Feb 19, 2011 20:14:38 GMT -5
This photo depicts a blue colored multi connector bus that looks to be re-soldered but the same "neck bolt" tech named Frank his last name Stein , lol It looks as if a large barrel red hot solder tip was smashed into this delicate little pin connector. It is located directly behind the front radio face and joins the vertical face board to the horizontal large main board via many small wire leg's running thru the blue connector ( my amateur description). You can see the date March 31 1978 embossed into the board along with the name "Stoner" made into the metal trace on the board, as each board, even the small board in the earlier photos also has the date embossed into them. Remember kids , if Your daddy drives a pick up truck with no doors on it don't let dad try to fix your highly collectible radio with his wire feed welder, also remind daddy that chewing tobacco juice is not solder flux, lol. Attachments:
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