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Post by Night Ranger on Mar 30, 2016 9:57:36 GMT -5
In keeping with the Zero-Five theme, I was wondering if we could post our personal experiences with failed radio equipment here. Not to seek any assistance with the repairs, just raise the awareness of radio equipment and how it goes BOOM! Photos of the 0-5'd equipment would be a bonus  I think my most exciting equipment blow-up occurred when I was restoring an old tan and brown D&A Raider. It looked pretty good, but it had numerous problems. The relay was making intermittent connections, and I sprayed it with contact cleaner. Apparently the plastic was already near failure and my contact cleaner pushed it over the edge. I also made the mistake of not giving the contact cleaner enough time for all of it to dry out. When I keyed the amp the relay arced and the contact cleaner fumes and remaining residue ignited. A big puff of blue flame rolled out of the bottom and in to the air. I turned it back off and put out the flames. After multiple part failures I did eventually make a nice working Raider out of it, but it made my heart skip a beat or two when it caught on fire.  This is the repaired and restored D&A Raider converted to cheap 22jg6a tubes  Night Ranger |
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Sandbagger
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Post by Sandbagger on Mar 30, 2016 10:30:53 GMT -5
In the spirit of "Ol Zero-Five", and the colossal meltdowns that often accompanied his projects, use this thread to post pictures and/or anecdotal accounts of some of your radio exploits gone horribly wrong. Radios, amps, antennas, you name it. Bonus points if smoke accompanied any of it.
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Post by BBB on Apr 1, 2016 9:24:15 GMT -5
Hopefully we can contribute our experiences and stay enrolled in the Zero-Five Institute of Technology for the betterment of the hobby. My latest course was Advanced MOSFET Replacement 101. The RCI 2970N2 Zero Five'd in fine fashion while transmitting a 10 watt AM carrier with an intermittently failing Coax jumper. Since I didn't have an SWR meter in line between the radio and the amp I was using, I didn't notice the issue until I heard a loud "Zorch-Thump-thump". That sound was two of the eight IRF520 MOSFETs literally blowing up inside the internal amplifier. I assume the 100 amp power supply and 40 amp radio supply fuse that didn't blow had something to do with the 0-5 nature of the explosion.  Attachments:
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Post by BBB on Apr 1, 2016 9:26:02 GMT -5
Some more of the situation:   See, there was some smoke with a spread of flying debris under the amp cover, haha. Good news is that a new set of eight MOSFETs from RF Parts I put in work fine. Had to repair some of the traces on the double sided PC board though. That was interesting. I was able to post up both underside and upper views of the amp board on my big LCD monitor. That was a big help. Just got to be mindful that MOSFETs are more sensitive to VSWR. |
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Post by BBB on Apr 1, 2016 17:14:25 GMT -5
I also bought a previously 0-5'd pristine looking Daystrom Heathkit HA-11 Warrior amplifier that I heard Gene had on lock-down. It came sans the (4) 811A tubes but it did come with a bonus charred plate choke  Maybe someday I'll test the choke and throw in some Chinese tubes to see if it survived the Zero Five treatment. Anyone got some 811As laying around they're not using? It's very heavy at 90 lbs, that's for sure. www.heathkit-museum.com/ham/hvmha-10.shtml |
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Post by Sandbagger on Apr 1, 2016 17:42:22 GMT -5
I also bought a previously 0-5'd pristine looking Daystrom Heathkit HA-11 Warrior amplifier that I heard Gene had on lock-down. It came sans the (4) 811A tubes but it did come with a bonus charred plate choke Maybe someday I'll test the choke and throw in some Chinese tubes to see if it survived the Zero Five treatment. Anyone got some 811As laying around they're not using? It's very heavy at 90 lbs, that's for sure. www.heathkit-museum.com/ham/hvmha-10.shtmlRemnants of "ol' zero-five" are scattered throughout the radio community. I have his Collins amp, also sans tubes (and the case). That's why I'm waiting for decent priced 572b's to show up. I'd like to get that amp up and running again. |
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Post by Sandbagger on Apr 1, 2016 18:06:48 GMT -5
Hopefully we can contribute our experiences and stay enrolled in the Zero-Five Institute of Technology for the betterment of the hobby. My latest course was Advanced MOSFET Replacement 101. The RCI 2970N2 Zero Five'd in fine fashion while transmitting a 10 watt AM carrier with an intermittently failing Coax jumper. Since I didn't have an SWR meter in line between the radio and the amp I was using, I didn't notice the issue until I heard a loud "Zorch-Thump-thump". That sound was two of the eight IRF520 MOSFETs literally blowing up inside the internal amplifier. I assume the 100 amp power supply and 40 amp radio supply fuse that didn't blow had something to do with the 0-5 nature of the explosion. View AttachmentThat seems like such a Mickey Mouse design, having to use 8 switching MOSFET's to do the same job as 2 RF bipolars. With 8 transistors, you have to make sure each one is balanced with the others. Switching MOSFETS have a VERY narrow linear range, which makes biasing tough. They also can't seem to handle a high SWR, as you found out. |
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Post by BBB on Apr 1, 2016 21:20:13 GMT -5
Hopefully we can contribute our experiences and stay enrolled in the Zero-Five Institute of Technology for the betterment of the hobby. My latest course was Advanced MOSFET Replacement 101. The RCI 2970N2 Zero Five'd in fine fashion while transmitting a 10 watt AM carrier with an intermittently failing Coax jumper. Since I didn't have an SWR meter in line between the radio and the amp I was using, I didn't notice the issue until I heard a loud "Zorch-Thump-thump". That sound was two of the eight IRF520 MOSFETs literally blowing up inside the internal amplifier. I assume the 100 amp power supply and 40 amp radio supply fuse that didn't blow had something to do with the 0-5 nature of the explosion. View AttachmentThat seems like such a Mickey Mouse design, having to use 8 switching MOSFET's to do the same job as 2 RF bipolars. With 8 transistors, you have to make sure each one is balanced with the others. Switching MOSFETS have a VERY narrow linear range, which makes biasing tough. They also can't seem to handle a high SWR, as you found out. That's exactly why I buy from RF parts, Confirmed same batch ordering and yes, unfortunately, you must replace them all at the same time from that same batch. They know what they're doing. Same folks have the new 572b available  |
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Post by BBB on Apr 10, 2016 10:22:36 GMT -5
Update, the RCI 2970N2 has been run for a few days now and the Final Bias is stable and properly set with no heat build up in the combiner resistors to hint of any imbalance between the two stages, plus now I have a few extra new MOSFETs that are used in the current batch of Galaxy Dual Final radios. I'm contemplating selling the 2970N2 and holding onto the older 2970 that's looking really good after replacing the old yellowed rubber push buttons with brandy new tidy whitey push buttons  |
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Post by Sandbagger on Apr 10, 2016 11:27:07 GMT -5
Update, the RCI 2970N2 has been run for a few days now and the Final Bias is stable and properly set with no heat build up in the combiner resistors to hint of any imbalance between the two stages, plus now I have a few extra new MOSFETs that are used in the current batch of Galaxy Dual Final radios. I'm contemplating selling the 2970N2 and holding onto the older 2970 that's looking really good after replacing the old yellowed rubber push buttons with brandy new tidy whitey push buttons View AttachmentHopefully your "old" 2970 is not a really old version, as that's the one responsible for us being on 28.412 on our SSB nets, as those old 2970's running on CB channel 29 put out one hell of a spur on 28.410..... and a bunch of other places. |
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Post by Deleted on Apr 12, 2016 19:54:56 GMT -5
I brought a TRC-457 back from the dead and had it working for about one day, and then I fried it. I could not get it back. I could not recall what caused it. But I was tried to undo all these mods and it went kaput!
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Post by MonkeyMan on Apr 13, 2016 11:12:27 GMT -5
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Post by 2600 on Apr 14, 2016 14:56:44 GMT -5
Here ya go! Lots of garage-built 'bowl boxes' use the 3-500Z without any cooling on the underside of the tube sockets.  Still has four out of five good pins, right? Kinda like that magic smoke. Putting the solder back into the filament pins of a 3-500Z just never quite works right. Never mind why. That's a story for another day. 73 |
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Post by 2600 on Apr 14, 2016 15:00:54 GMT -5
I sure do have a lot of these pics. This amplifier suffered a line surge when lightning hit the owner's utility pole feeding the house.  Makes me wonder if a ceramic-body fuse would have exploded like this glass one. Somewhere I also had a pic of the power switch from this amplifier. I'll have a look for it. HAH! Found it!. Remember the old public-service spot "This is your brain on drugs"? Well, this is your amplifier on lightning.  73 |
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Post by Night Ranger on Apr 14, 2016 17:58:28 GMT -5
Here ya go! Lots of garage-built 'bowl boxes' use the 3-500Z without any cooling on the underside of the tube sockets. Still has four out of five good pins, right? Kinda like that magic smoke. Putting the solder back into the filament pins of a 3-500Z just never quite works right. Never mind why. That's a story for another day. 73 Even on my Drake L-4B and my Henry 2KD-5 I've learned to let the blower run for about five minutes after talking on it before turning the amp off for that very reason. Night Ranger |
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Post by Sandbagger on Apr 14, 2016 19:14:12 GMT -5
Here ya go! Lots of garage-built 'bowl boxes' use the 3-500Z without any cooling on the underside of the tube sockets. Still has four out of five good pins, right? Kinda like that magic smoke. Putting the solder back into the filament pins of a 3-500Z just never quite works right. Never mind why. That's a story for another day. 73 Even on my Drake L-4B and my Henry 2KD-5 I've learned to let the blower run for about five minutes after talking on it before turning the amp off for that very reason. This is right up "Ol' Zero-Five's" alley. This is what happens when you push an amplifier, that's designed primarily for SSB, in a full carrier mode, and do it for a duty cycle that's far too long. Extra cooling, and a change in bias can help to reduce the heat. But the best thing to remember is that the continuous duty power rating for tubes like that is usually less than 50% of its full rated power output. But try telling that to the all knobs to the right set............ |
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Post by MonkeyMan on Apr 14, 2016 21:12:55 GMT -5
At one point during the Ol' Zero Five days I was antagonizing Spitfire pretty much on a daily basis. One freezing cold morning I went out to start Super Truck II for her to warm up and out of habit I grabbed the mic and started hollering "Pete! Pete! Pete!" About two seconds after I unkeyed I realized something was very wrong. I smelled smoke. I believe a relay in the amp (Firebird, a 1 pill I think) crapped the bed but I never investigated further. Long story short, the amp, my TRC-485 and my pride all went up in smoke. Thank goodness I realized what was going on before I walked back into the house. |
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Post by Sandbagger on Apr 15, 2016 7:00:58 GMT -5
At one point during the Ol' Zero Five days I was antagonizing Spitfire pretty much on a daily basis. One freezing cold morning I went out to start Super Truck II for her to warm up and out of habit I grabbed the mic and started hollering "Pete! Pete! Pete!" About two seconds after I unkeyed I realized something was very wrong. I smelled smoke. I believe a relay in the amp (Firebird, a 1 pill I think) crapped the bed but I never investigated further. Long story short, the amp, my TRC-485 and my pride all went up in smoke. Thank goodness I realized what was going on before I walked back into the house. I believe that's called "Karma", even if it was in a truck (Would that make it "Truckma?")  |
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Post by MonkeyMan on Apr 15, 2016 8:46:01 GMT -5
...if it was in a truck (Would that make it "Truckma?")  |
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Post by Sandbagger on Apr 15, 2016 8:48:02 GMT -5
I really don't have much to contribute to this thread, since very few pieces of my equipment have ever fried while I was using it. The closest to this would have to be my Midland 13-885  In 1975, this radio belonged to a friend of mine who lived diagonally across the street. His antenna was 60' up and it was the unfortunate victim of a lightning strike. The lightning vaporized the loading coil in the antenna, melted the feedline right out of the connector, and fried the radio. Long story short, my neighbor was unable to fix the radio, so he traded me the Midland for a TRC-47 that I had which had a problem with AM transmit. I was able to bring the Midland back from the dead. It needed audio power output transistors, a regulator transistor in the power supply, and a new choke right off the antenna jack. I used the radio for several years, until I lent it to my father-in-law, who used it for a while. While in his possession, a water main broke in the street in front of his house, and it ended up flooding the entire basement (the water was literally up to the top steps in the basement), which submerged his entire radio station, including the Midland. When we went through the damage, I took the Midland outside and opened it up. It was literally loaded with mud (I started calling it the "Mudland" at that point). I actually blasted the whole radio with a water hose and cleaned it out and let it bake in the sun. Amazingly enough, it came back to life, although shortly afterward, the S-meter and the clock started having issues which necessitated eventual replacements. But that radio survives to this day, and makes occasional appearances on CRR. The only radio that "fried" as a result of my handiwork, was a brand new Courier 23 channel PLL Centurion, that I worked on back in late 1976. It belonged to one of the locals, and he wanted me to put channel "22A" in the blank spot. Unlike older crystal radios, PLL circuits did things differently, and I was still learning how they worked. Long story short, I must have accidentally shorted one of the programming pins of the upd858 PLL and it became stuck "Hi". The result was interesting. He lost a bunch of the "normal" channels, but in its place were a bunch of new channels above channel 23. Needless to say, the owner did not think this was a reasonable trade. But lucky for me, he was able to send the radio back to the factory, and they actually gave him back a 40 channel version, since they had just became legal. So he ended up making out on the deal. Oh, and there is my TRC-448, which I had back in the early 80's. The radio was really a junk design from the get-go (which probably explains why the radio didn't last more than a year in production). The radio had a major flaw in that if you switched the mode switch from AM to USB while you were keyed, it would pop the final transistor out. I must have gone through about 5 or 6 1307 finals before I got it in my head not to do that. Thankfully, I used to buy 1307's in bulk direct from Japan for $2 a piece back then, so it wasn't an expensive lesson. |
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Post by BBB on Jun 6, 2016 19:54:30 GMT -5
I sense a great disturbance in the 0-5 Galactic Force ... like Spitfires 480HX and Badgers Fl-2100B all crying out at once. Just 0-5'd two runs of my pristine LMR400 coax with the gas hedge trimmer. Cut thru 'em like butter. One was the main feed to the 11 meter Sirio 2016 and the other went to my 2 meter/440 dual band Comet base antenna. Darn it, I despise barrel connectors on outdoor stuff     This thread should have its own board listing title IMO  |
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Post by Sandbagger on Jun 6, 2016 21:11:46 GMT -5
I sense a great disturbance in the 0-5 Galactic Force ... like Spitfires 480HX and Badgers Fl-2100B all crying out at once. Just 0-5'd two runs of my pristine LMR400 coax with the gas hedge trimmer. Cut thru 'em like butter. One was the main feed to the 11 meter Sirio 2016 and the other went to my 2 meter/440 dual band Comet base antenna. Darn it, I despise barrel connectors on outdoor stuff View AttachmentThis thread should have its own board listing title IMO Well, you have to affect a quick repair in order to be ready for CRR Wednesday night...... Unless we want to make it a Mobile theme based night where we all jump out in the mobiles and do it up with vintage mobile equipment........ That sort of leaves Pete out though since he doesn't have a mobile in his zipper car....... I wonder if this is 0-5 karma for poking fun at him during the SNUBWAP last night. Maybe you've played that Barbie-Girl clip once too many times.... Or maybe Cousin Brucie has dug up those Voodoo dolls again...... |
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Post by BBB on Jun 11, 2016 8:50:24 GMT -5
I sense a great disturbance in the 0-5 Galactic Force ... like Spitfires 480HX and Badgers Fl-2100B all crying out at once. Just 0-5'd two runs of my pristine LMR400 coax with the gas hedge trimmer. Cut thru 'em like butter. One was the main feed to the 11 meter Sirio 2016 and the other went to my 2 meter/440 dual band Comet base antenna. Darn it, I despise barrel connectors on outdoor stuff View AttachmentThis thread should have its own board listing title IMO Well, you have to affect a quick repair in order to be ready for CRR Wednesday night...... Unless we want to make it a Mobile theme based night where we all jump out in the mobiles and do it up with vintage mobile equipment........ That sort of leaves Pete out though since he doesn't have a mobile in his zipper car....... I wonder if this is 0-5 karma for poking fun at him during the SNUBWAP last night. Maybe you've played that Barbie-Girl clip once too many times.... Or maybe Cousin Brucie has dug up those Voodoo dolls again...... Really can't play the Barbi song anymore as the 0-5 Gate that Spitfire played the other night reveals a similar yet different song. Maybe he can PM me 5 minute the clip where the song is played and I can determine what it actually is. |
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Post by BBB on Aug 18, 2016 10:27:20 GMT -5
Had a wake up call last night during Classic Radio Round Up when my Kris 23+ t00b CB went Ker-POW! Then a puff of smoke came from underneath the chassis  Not really enough to set off the smoke detector thankfully. It was in receive mode and kept receiving for a second until I could twist the power switch and yank the cord. An old original Atlas .470uf capacitor emptied out like a metallic steamer, haha. I'm assuming it's at least a 500 volt cap although it says CP-C600WV on it.  I highlighted the bad cap location. You can see it opened and the metallic foil unwound. The oil explosion residue can be seen on the bottom of the case cover just off to the left of the main chassis. |
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Post by BBB on Aug 22, 2016 17:56:11 GMT -5
The WV on the cap stands for Working Voltage, same as the regular Voltage or V rating. It tried to trick me, so a 600 volt cap is in order.
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Post by BBB on Feb 26, 2017 16:23:00 GMT -5
I ran a Stryker 955 as I sometimes do for the second half of CRR last week. Later, after hours while talking with "Wrench" with normal modulation and a 7 watt dead key swinging to 30 watts, a generous amount of smoke started pouring out the back. Magic smoke that is so I shut it down immediately. I cracked the factory warranty seal then opened it up and sure'nuff (2) of those (4) MOSFET FQP13N10 finals toasted. No Bad SWR, no excessive drive, no over-voltage, no overheating... just stinky smoke. I have a spare 955 that I put inline and continued talking to "Wrench" with, no problems at all so the system as a whole was fine. No excuse for the magic smoke other than $3 Chinese parts failures. The two right final FQP13N10 MOSFETS are toast. The two identical pre-drivers on the left look okay but I'll replace all four.  |
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Post by Sandbagger on Feb 26, 2017 19:33:12 GMT -5
I ran a Stryker 955 as I sometimes do for the second half of CRR last week. Later, after hours while talking with "Wrench" with normal modulation and a 7 watt dead key swinging to 30 watts, a generous amount of smoke started pouring out the back. Magic smoke that is so I shut it down immediately. I cracked the factory warranty seal then opened it up and sure'nuff (2) of those (4) MOSFET FQP13N10 finals toasted. No Bad SWR, no excessive drive, no over-voltage, no overheating... just stinky smoke. I have a spare 955 that I put inline and continued talking to "Wrench" with, no problems at all so the system as a whole was fine. No excuse for the magic smoke other than $3 Chinese parts failures. The two right final FQP13N10 MOSFETS are toast. The two identical pre-drivers on the left look okay but I'll replace all four. View AttachmentMost likely due to improper bias setting. That's what I hate the most about trying to make switching MOSFETS work as RF amplifiers. The linear range in these devices is so (deliberately, they're designed to be switchers) narrow, that the bias setting becomes critical. That's why there are so many of these types of failures with these radios. I'd never buy one...... The good news is that the devices are dirt cheap, so you can get a fresh supply of magic smoke to let out at yet another date...... |
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Post by BBB on Feb 27, 2017 19:44:03 GMT -5
Although the devices lasted a few years, I'd second that motion of the bias too high from the factory. Happened to the first round of RCI 2970N2s. When my N2 Zero-5d, I used the updated lower settings. 67 cents each...LOOK OUT  |
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Post by BBB on Jan 4, 2018 14:47:26 GMT -5
While in the process of restoring a Heathkit SB-220 amplifier and upon the second power-up, one of the 3-500z tube's 1mh 100ma grid chokes immediately melted. It let off some magic fan blown smoke with a lovely burnt varnish aroma. I'm in the process of trouble shooting it and I'm not sure what caused it yet...  |
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Post by SIX-SHOOTER on Jan 4, 2018 22:32:14 GMT -5
I have been playing radio since 1965 & I have never once fried a piece of gear that cost more than a few dollars so that it was repaired.Bad cap,diode popped,tube shorted,or just a blown fuse it has always been a pretty simple fix.Some were my fault & others were just normal failures from age.I stressed over several & found out the stress was not worth the cost of the minor repairs.Guess I have been very blessed but I can live with that & even more so if the rest of my time here goes as well for me & my radio gear on the Ham Gear & CB Gear.
SIX-SHOOTER
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Not really enough to set off the smoke detector thankfully. 
