This is the same board that was dishwashered in the last thread on that topic, and the dishwasher is my plan for this board again - it's too small for the car wash ..... 
Win W5JAG
Yes, with detergent, but not a lot.
Edit: I know what you mean about not finding things - I have most parts binned, but I still have boxes and bags full of stuff and only vague recollections of what I've bought. When i was looking for a test OPT for the 801's, I opened a small box that I thought had some cheap 7K's in it - it had a matched set of McCoy USB and LSB crystal filters and the carrier crystal. That was a nice find.
Win W5JAG
Yes, with detergent, but not a lot.
Edit: I know what you mean about not finding things - I have most parts binned, but I still have boxes and bags full of stuff and only vague recollections of what I've bought. When i was looking for a test OPT for the 801's, I opened a small box that I thought had some cheap 7K's in it - it had a matched set of McCoy USB and LSB crystal filters and the carrier crystal. That was a nice find.
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I learned the hard way that lacquer thinner wrinkles the green solder mask and makes the white silkscreen peel.
I haven't tried the dishwasher yet, but the stuff in some dishwashing detergent is rather alkaline. I'm not sure that I want some of the crud that's on my board associating with things I eat off of.
I have set a couple of resistors on fire, and blown a few electrolytics on my old test board, I used a toothbrush and WD40 on it a couple of times too.
Maybe it's time for a new test board.... maybe the board in my industrial amp if I make a new one. It's rather discolored from 6 years of overheating. That amp got too hot to touch when it ran all day. It was the speaker amp on my PC for a couple of years.
I haven't tried the dishwasher yet, but the stuff in some dishwashing detergent is rather alkaline. I'm not sure that I want some of the crud that's on my board associating with things I eat off of.
I have set a couple of resistors on fire, and blown a few electrolytics on my old test board, I used a toothbrush and WD40 on it a couple of times too.
Maybe it's time for a new test board.... maybe the board in my industrial amp if I make a new one. It's rather discolored from 6 years of overheating. That amp got too hot to touch when it ran all day. It was the speaker amp on my PC for a couple of years.
I never really thought much about it before that last thread. I try to be circumspect about how I do it and what I put in it, but I've never had a problem that I could trace to that.
This board may have already been dishwashed 2X. For sure 1X.
It's a lot more gentle than the car wash.
It's good on small car parts, too - if the woman of the house is out of town ....
Win W5JAG
This board may have already been dishwashed 2X. For sure 1X.
It's a lot more gentle than the car wash.
It's good on small car parts, too - if the woman of the house is out of town ....
Win W5JAG
After you posted that a while back, I tried putting some tubes in a tray with a snap on perforated lid and running them through the old dishwasher we had in Florida.
These were extremely nasty 7 and 9 pin miniature tubes that I had thousands of. They came out shiny, but the caustic detergent made the already corroded pins very brittle and many snapped off when put into a socket. WD 40 and a toothbrush with an alcohol rinse was the best process I had for cleaning up the better specimens.
They came from the same 100,000 tube lot I got with all the smashed 807's. They were stored in a rotting warehouse for at least 10 years, and discovered when the dozers came to tear down the building. I got them all for about 3 days labor cleaning out the place. At least half of the tubes were tossed in the trash, given away, used for target practice, or purposefully blown up with excessive voltage.
These were extremely nasty 7 and 9 pin miniature tubes that I had thousands of. They came out shiny, but the caustic detergent made the already corroded pins very brittle and many snapped off when put into a socket. WD 40 and a toothbrush with an alcohol rinse was the best process I had for cleaning up the better specimens.
They came from the same 100,000 tube lot I got with all the smashed 807's. They were stored in a rotting warehouse for at least 10 years, and discovered when the dozers came to tear down the building. I got them all for about 3 days labor cleaning out the place. At least half of the tubes were tossed in the trash, given away, used for target practice, or purposefully blown up with excessive voltage.
Cleaned up fairly well. Not like new by any means, but this board is still very servicable. It's earned the right to look rough.
This is after another trip through the dishwasher, removal of most of the larger components, and about a quarter ounce of solder that had accumulated over the years. There is a lot of hard, crusty, flux residue left. It looks like Hades, but is not hurting anything. Since thinner can damage the board, I'll probably just leave it be, unless there is something that can remove it without damaging the board.
Win W5JAG
This is after another trip through the dishwasher, removal of most of the larger components, and about a quarter ounce of solder that had accumulated over the years. There is a lot of hard, crusty, flux residue left. It looks like Hades, but is not hurting anything. Since thinner can damage the board, I'll probably just leave it be, unless there is something that can remove it without damaging the board.
Win W5JAG
Attachments
Certainly looks like a trip to the dishwasher did your board some good !
Hi Win W5JAG,
I mentioned earlier in this thread that I use socket adapters with 6BG6 tubes in the SSE.
The 6CD6 has the same 5BT pinout as the 6BG6, so can the 6CD6 be used with same adaptor
without any other modification ?
Another tube with the same 5BT pinout is the 6EX6, is this also a suitable tube for the SSE ?
Thanks.
No.
The pin out is the same, but the screen voltage will be too high for 6CD6 in a stock SSE.
The 6CD6 will try to draw a LOT of current because of the high screen voltage. You might be able to increase the cathode resistance enough to pull it back down, but you will probably exceed the voltage rating of your existing cathode bypass caps in the process. This is the same problem seen when trying to run 6BQ6 and 6DQ6 in an ordinary SSE, or trying to sub in a 6384/6AR6/6098 for a 6L6GC, etc.
If you try this, your low power SSE would be the most likely candidate for success, since it will obviously present the lowest screen voltage, but I would have it metered and watch it like a hawk. You will definitely have to experiment. It won't be plug and play.
You might have a better chance of getting away with this in UL. In playing around with the child resistant SSE, I did notice that some tubes, with sensitive screen grids, seemed to be less sensitive in UL. In other words, they worked in UL when I didn't expect them to. I don't have an explanation for this, it's just what I observed.
The sweeps, including 6146, really need to be run as pentodes, with a separate, much lower voltage, screen supply, to take advantage of their power capability. There are some notes on sweeps in general, and 6CD6 in particular, on Tubelab's site. He can probably answer this better than I.
I am not familar with 6EX6. Look at the screen voltage rating. That's your starting piece of information .....
Win W5JAG
The pin out is the same, but the screen voltage will be too high for 6CD6 in a stock SSE.
The 6CD6 will try to draw a LOT of current because of the high screen voltage. You might be able to increase the cathode resistance enough to pull it back down, but you will probably exceed the voltage rating of your existing cathode bypass caps in the process. This is the same problem seen when trying to run 6BQ6 and 6DQ6 in an ordinary SSE, or trying to sub in a 6384/6AR6/6098 for a 6L6GC, etc.
If you try this, your low power SSE would be the most likely candidate for success, since it will obviously present the lowest screen voltage, but I would have it metered and watch it like a hawk. You will definitely have to experiment. It won't be plug and play.
You might have a better chance of getting away with this in UL. In playing around with the child resistant SSE, I did notice that some tubes, with sensitive screen grids, seemed to be less sensitive in UL. In other words, they worked in UL when I didn't expect them to. I don't have an explanation for this, it's just what I observed.
The sweeps, including 6146, really need to be run as pentodes, with a separate, much lower voltage, screen supply, to take advantage of their power capability. There are some notes on sweeps in general, and 6CD6 in particular, on Tubelab's site. He can probably answer this better than I.
I am not familar with 6EX6. Look at the screen voltage rating. That's your starting piece of information .....
Win W5JAG
Okay, Thanks Win.
I was asking mainly because these tubes are relatively cheap at $5 - $7 from some online suppliers.
I do have a spare power transformer that can give me a B+ from around 160 to 240 volts depending on the
rectifier and power tube in use but the 6.3V filament supply is only rated for 4A while these tubes require
a whopping 2.5A each.
I'll probably revisit this sometime in the future.
I was asking mainly because these tubes are relatively cheap at $5 - $7 from some online suppliers.
I do have a spare power transformer that can give me a B+ from around 160 to 240 volts depending on the
rectifier and power tube in use but the 6.3V filament supply is only rated for 4A while these tubes require
a whopping 2.5A each.
I'll probably revisit this sometime in the future.
My experiments on a 6CD6 in triode at voltages above 300 volts didn't end well. Even if it works initially, the tube may go into runaway some time in its future.
I never went very far with the 6CD6, but I built a triode amplifier with 6LW6's on 400 volts several years ago. After 4 tube failures in just over a year, I gave up and dismantled it. The failures were all red plate / arc over runaways that came quickly without warning. The amp would be playing, and then there would be a faint hum, then a loud hum, then a red plate and a blown fuse. All of this happened in less than a minute. The tubes did not work right even at normal voltages after that.
I never went very far with the 6CD6, but I built a triode amplifier with 6LW6's on 400 volts several years ago. After 4 tube failures in just over a year, I gave up and dismantled it. The failures were all red plate / arc over runaways that came quickly without warning. The amp would be playing, and then there would be a faint hum, then a loud hum, then a red plate and a blown fuse. All of this happened in less than a minute. The tubes did not work right even at normal voltages after that.
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