[Eliot Ness]

You did a beautiful job on that one Bob, it looks fantastic, Powel would be proud

[klondike98]

I am back to look at the third stage of this Crosley. If you are following my Thompson H-3 speaker thread you'll know that I think I repaired the speaker but got no sound when I connected to this Crosley Trirdyne.

Mr. Fixr55 suggested putting my headphones (with which I could hear the broadcast but it only use stages 1 & 2 on the Crosley when you plug into the headphone jack) across the speaker connections. I did that and while I heard a slight buzz indicating the headphones were picking up something, there was no sound from the broadcast I was playing on my SSTran transmitter. I fiddled with the 3rd 01A tube and realized that it is not sitting in the socket correctly. After a little manipulation and a small shim to hold the tube in place I saw the filament light up but unfortunately still did not hear the broadcast.

My next step will be to take the chassis back out of the cabinet, clean the contacts on the headphone switch, reflow the solder on the connections of the third stage and take a better look at the socket. Stay tuned....

[MrFixr55]

Hii Bob,

Definitely check the headphone jack. The Tridyne is a reflex set, where the 1st RF amp is also the 1st AF amp. With the headphone plug in the jack, the switch is open and the Phones are in series with the RF Output coil primary. With the plug unplugged, the switch puts the primary of the 2nd AF transformer in series with the RF transformer primary, thereby connecting the RF / 1st AF to the 2nd AF.

If course, if the primary or secondary of the 2nd AF transformer are bad, the 2nd AF will be dead.

[Eliot Ness]

Bob, that vintage battery set is notorious for open transformers so take a good look at #7 on the schematic.

[MrFixr55]

Hi Bob,  
I think you have the schematic from this site:

Crosley Trirdyn (crosleyradios.com)

The schematic may be drawin by someone other than Crosley.  The pictorial schematic is likely the correct one.  I think that the schematic in the above website is incorrect for the headphone jack.  The frame is connected to +90V.  The tip contact should be connected to the RF Output transformer primary.  The switch contact should connect to the AF interstage transformer primary.

The following doc is from the Nostalgia Air site. I think that the hand drawing for the Tridyne from the N/A site is correct.  However, look at the 5-38 diagram 0n the same page.  The plate of the 2nd AF is connected directly to B+, so that diagram can't be correct.  We can't contact the person who drew the diagram at Rider unless someone knows how to contact Heaven.

Crosley Tridyne 51 5-38.pdf Size: 326.52 KB  Downloads: 102

I have to apologize, I can be obtuse in my entries.  Back in my Field Engineer days, I had to write a monthly technical report.  These were hand written as this was the 1980s before affordable laptop computers, and I did not have a typewriter.  My reports were hand written and then sent to the district sec-  Oops, admin assistant.  I may have driven her to drink.  I would get a call from my boss stating that Donna is trying to type my report but could not do so because someone borrowed the Rosetta Stone.  He would then ask how I got through 11 years of Catholic educations and earned a Bachelor of Science degree from college with that handwriting.

[klondike98]

Thx guys. I did check the transformers in the beginning but will do so again...never know, something can always go wrong. I may be a few days before I can get back to it but will report on progress. Thx also for the headsup on the schematics.

[Chas]

When working with ANY reflex and its original audio transformer(s) do note the existing connections of Plate, B+, Grid, C-. MOST reflexes require a reversal of either the plate side or grid side for the radio to operate properly, if connected incorrectly the transformer can invert the signal incorrectly and cause the radio to oscillate at an audio rate. If that happens either transformer and either winding must be swapped. Swap only one winding on any transformer. As for those who did not experience this issue, Luck... Some reflexes also require the core/frame to be connected to ground or A-, simply repeat what you see.

As for transformers that have had the core replaced, do the swap inside the shell so bus wiring remains the same...

Chas

[Radioroslyn]

This is what I do when I use the replacement bobbins to figure out the phasing. You can also use the whole winding rather than just 1/2.

[klondike98]

Thanks for the info guys. Turns out there were two issues, both relatively simple. First the contact on the headphones jack and second the sloppy socket connection on the third 01A tube. I gave the contact a really good clean and readjusted the shim I've used on the socket. I tried bending the socket contact plates upward a bit to help with contact but did not want to do too much for fear of snapping one off. The shim is not very elegant, but it works.

[Image: https://www.dropbox.com/scl/fi/4biesax48...e50v&raw=1]

Now I'm able to hear broadcasts through both the headphones or the speaker. If you would like to hear the radio and speaker playing, click on the video link below.

[Video: https://youtu.be/59QSypuYYL4]

[MrFixr55]

GREAT!! looks great, sounds great. Maybe a metal shim at the base of the tube and filling in any wornplastic from the bayonet notch will fix the socket. Worst case, for display purposes, remove the spring clips and solder wires from the screw contacts to the tube pins. Or get a1920s vintage lollypop stick to keep it real. Another great Bobs restoration and another piece of history saved!