[Radioroslyn]

Came home late from work after picking up Tom's 37-116 an am bushed!! Hopefully will finish the power supply over the weekend (mine is Sun-Mon).
Terry ZZZZZZZZZ

[Radioroslyn]

Was able to spend a few hours on the Crosley and p/s. Finish up the p/s except for a terminal strip. I add regulator to the filament buss so it is adjustable from 1.2v to 5v. Under load I'm getting about a 2.5v drop across the regulator. Will have to look into that to see it I can jack it up a little. On the b+ side of things I had 7K tied across the 220v buss It was running a little hot so I added another 5K in series with the 7K which work very well. At the top of the 7K resistor I had 140vdc and was able to set the taps a 90 and 22v without a problem.
Onward to giving it a try on the radio. So I hooked up the filament to see if I could get the tube to light. When I attached the wires to the circuit the 6v dropped to 0. Hmmmm Check thing over and found that I had wired the regulator wrong. Correct the problem and now all is good well almost. Two of the three tube where lit. Hmmmm Tried another tube, didn't fix it. Started to measuring voltages and found that the heavy buss wire had broken away the connection at the socket. Resolder the connection and all was good so far.
http://www.flickr.com/photos/53710524@N06/10544855416/
More Later
Terry

[Radioroslyn]

Awhile back I post that the grid leak resistor was bad (open) well tonight I thought I'd put the power to old gal and see if she jumps with excitement. I went downstairs to grab suitable replacement for the 'leak. Broke out the little red digital meter to double check the replacement. Got a 2M job and measured it. It measured open too Hmmm. Looked at the scale on the switch and it said 2000K and I thought sure sounds like a lot of ohms don't it?? I did some quick math on a piece of paper and little red meter will only read up to 2M. Well what do you know!! Went over to the bench and flipped on the old Heathkit V4 VTVM which will measure up the 100M. Don't know how accurate it is at 100M. Let it warm up for a few minutes it measures the 'leak at 5.3M. Perfectly fine for the grid leak. Generally speaking the higher the resistance of the GL the sharper the selectivity. So the old grid leak resistor is ok. The Mrs will be home soon so I better pickup my junk out of the living room. Hope she won't see the solder flicks and burn mark in the carpet.
More later
Terry

[Radioroslyn]

Had a little spare time at the shop today so Mr Mohawk paid a visit to Mr Crosley's cabinet. It's looked pretty bad ( that's an odd statement,oxymoron??). Lots of wear and the top has some discolorations. Mr Bix did a striptease on the top and it looks much better but still has large blackish stain. Mr Mohawk was able to do wonders for the rest of the cabinet. It looks quite good now but still needs a little burn in work on some small nicks on the edges. Will post some pics later, back is killing me! May pull out the tuning condenser for the detector stage and give it a good cleaning. On any set it is important that the tuning condenser make good connection at the rotor and the stator. Without this it can cause a lot of problems with the detector not wanting to oscillate or can cause intermittent problems that can make your hair smoke.
More Later
Terry
ps While I was at work I was able to visit a friend of mine and was able to talk him out of a 112A tube which will work nicely in the Crosley's audio output stage. Also managed to get a WWII aircraft transmitter's screen grid modulator too. I kinda handy 'cause I have the transmitter that it goes with (BC-696 transmitter and BC-456 modulator) It also came with the 28v dynomotor that takes 28vdc and turns it into 550vdc.

[Radioroslyn]

Well hooked up the power supply and put the power to it. Everything seems OK no smoke or funny smells. The tuning acts like it's intermittent so the tunings condensers need to come apart for good cleaning. The detector seems to be working as I can adjust the regeneration and it will oscillate. So will clean up a few things and report back later. If I'm lucky I maybe able to catch the second half of War of the Worlds if it's on the air here in the east.
Terry

[Radioroslyn]

Cleaned up the condenser on the right side. That one is the more critical one. It would be considered the main tuning it tunes the detector stage which controls the frequency that the set receives. The condenser or the left tunes the RF stage which will make the received signal louder.
With it cleaned up and a few more solder joints resolder I reapplied power and was rewarded with reception!! Got all the locals and WOR out of NY. Line noise here is kinda high. Everything seems to be working as is should. The RF tuning has a dead spot but there again probably a dirt issue.
Plugged in the 112A in the output stage, was using a 201A and make a big difference. Audio was much cleaner sounding. I am using a rather small output transformer out of a cheap AA5 set. If it had some more iron to it it to would improve the sound. The 112A is probably good for a few hundred milliwatts with 90v on the plate and 4.5 on the filament.
I didn't mention that a previous owner had soldered a jumper from C+ to C-. This was done to eliminate the C battery. Bad move plays much better with a C battery. I'm using a 9V job. Still need a little adjusting I think the grid leak is a little too high in value as it tunes pretty sharply. With it's own battery pack that should help with some of the noise I'm getting.
Terry
I'll see if I can catch Zoomer on 740 out of Ca

[Radioroslyn]

At 10:00 I was able to tune in War of the worlds out of CA and did hear about 2/3 of it before the band went south.
Terry

[morzh]

Nice! Congrats!
Why did the band go south?

[Radioroslyn]

To get to the other side or to hold it's pants up. I forget which one.
Terry

[Eric T]

Must be looking for warmer climes...

[Radioroslyn]

Snapped it on the next evening to see what I could hear and it wouldn't pickup anything! Now I know this thing is no vacuum but should hear something! Work on it for about an hour trying to find the problem. Everything looked ok and all of the voltages where what they should be. It was pretty frustrating but I did finally did find the issues. The antenna was disconnected!! Hopefully I'm not the only one that misses the simple.

A good friend of mine services computers and he is nice enough to save the dead power supplies for me. Now doesn't sound like much but I find them to be a little treasure trove of goodies. Most will have some good sized diodes, plastic covered wire in many colors, and some good sized electrolytic capacitors. Parts from one was what I used to build the power supply for this set except for the transformer and adjustable regulator.

I revised the power supply by adding a full wave bridge rectifier to the filament supply. I was using a half wave but thought that the bridge would give me a bit more output voltage. A computer p/s yielded a nice 800v@4A bridge. After incorporating it I didn't get the desired result. Still was getting about 4.8vdc out. I'm getting a little better than a 1 volt drop across the regulator. Now theory sez the with the half wave rectifier I should get about 5.5vdc output to the regulator (6.3vX.9) With the full wave bridge I should have 9vdc output to the regulator(6.3vX1.4). But in real life I still have total output of 4.8vdc out of the regulator. Now that isn't real bad as the tubes are rated @ 5v/250ma each. Can certainly use this supply for other sets that have 1.5 to 5v filament with a twist of a knob. If anyone is interested I'll post a diagram of the revised p/s.

Will post some more pic's but need find to with the memory card.Don't know why they call it that it doesn't help me remember it. Did find a barrier strip.
Terry

[Radioroslyn]

Sorry for the loooooong break but have been in the middle of some house remodeling which is sorely needed. I have finished up the p/s as good as it is going to get. Filament voltage is a little low. At full till I'm getting about 4.8vdc. It heats the tubes fine but I think the transformer doesn't have enough current to give 5 or 6volts. The HV is fine. Can crank it up to 145v or so. Which is great for the 112A output tube.
Did some T/U work on the cabinet. Bleached out the dark spots on the lid, grain filled it,toned it and clear coated it. Looks great but I don't like the color. It's too red needs to be more yellow. So I will end up redoing it to get the color closer to the original.
Electrically I think it's about done as it's working well other than I may change the value of the grid leak resistor. Now it's about 5.5megs will try something around 2meg. Still is pretty dirty with the black crud. I cleaned the important parts the rest is for looks.
Will post some more pic's soon. Right now I have the living room,master bed room and two bathrooms apart. So the joint here is really a mess!!!
Will get back to it soon! Next project is my old EF Johnson Viking II. it's a 100watt AM/CW ham transmitter from 1953. Can post my progress with it if any one has an interest?? It's not a resto but just get it going again. Everything seems to work but no output power.
Terry

[morzh]

Terry

If you publish the "was" and "is" sch of your powwer supplies we could try to figure your woes.....otherwise I could only guess how and what you hooked up.

[Radioroslyn]

Well I took a few minutes to download a few pics of the progress so far. As I mentioned did some cabinet work to get better looking. Sorry lighting is awful because of the construction work. Here's some before (about 10) http://www.flickr.com/photos/53710524@N06/11198612603/
and after: http://www.flickr.com/photos/53710524@N06/11198452535/
I'm not real happy with the color of the top it's too red so I'll probably redo it at some point. For now I'm busy with the house so after new year I'll revisit it.
Terry
ps Mike the transformer just doesn't have enough kva's to run the fills at a higher voltage. 4.8 is only 2/10's low. NBD
pss. Found the problem with the Viking II power to the antenna relay was disconnected. Works fine now with a full 100watts output.

[Radioroslyn]

Kinda of an old thread but I ran across this article from 1925 about the old Trirdyn. Starts on pg 15
http://www.americanradiohistory.com/Arch...-04-11.pdf

Terry