[klondike98]

I opened up the Crosley from the Bandon Historical Museum that I'm working on. It has had a mouse in it at some point but I don't think it was there for very long. So far the best schematic I've been able to locate is: https://crosleyradios.com/battery-sets/TRIRDYN-1.pdf

[Image: https://www.dropbox.com/s/64g70xt8zrpv2z....jpg?raw=1]
[Image: https://www.dropbox.com/s/kcxf37car7o3hk....jpg?raw=1]

There are not a lot of components to this set and the "wiring" is mostly metal rod. I did have two places where the soldering had failed. One was where the jack for the headphones makes a connection and was easily repaired. The second was the solder connection between the C- connector on the top side of the set and the metal rod "wire" under the set. It also had a very unusual extra wiring that you can see in the photo below. At first I thought it was simply a piece of wire that had gotten caught in the set but then as I pulled at it the two loops of small wire separated and were clearly soldered to the C- on the left and the A- on the right. That can't have been original I think. The schematic's pictorial drawing seems to show A- and C- connected with a dotted line. Perhaps that connected is made under certain operating conditions.
It would seem easier to just jumper them on the topside of the set where there are nice wire connectors. Any thoughts?

[Image: https://www.dropbox.com/s/saok5i5c0f4ftk....jpg?raw=1]

The component labeled #16 in the set is a parallel resistor and capacitor. I think the capacitor is OK at least as well as I can measure it but the resistor is open. Unfortunately the schematic does not give a value for the resistance. I would "guess" it has to be something like 2meg or so...any ideas on its true value?

[Image: https://www.dropbox.com/s/9mbsadyziiq7ec....jpg?raw=1]

At the moment I don't have any way to listen to this set since I have no headphones or a working speaker for it. I'll be rewinding the Thompson speaker coils but that will be awhile down the road. I hope to find a set of headphones on ebay that are working.

[Ron Ramirez]

Bob

It appears to me that the dotted line between A- and C- terminals in the pictorial diagram was intended to be connected only if no "C" battery was used. Maybe someone didn't want to use a "C" battery and added the thin wire jumper?

Regarding the mystery resistor in parallel with the capacitor - It is a grid leak resistor, typically 2 to 5 megohms in value. Others may have differing opinions but I would use a 2 megohm resistor as a replacement - if you can figure out how to replicate the original, or how to take it apart.

[MrFixr55]

Hi Bob,

I know that you are an expert. You have done some fantastic restos, but the following is important for anyone who does restorations, especially at our age (at least some of us). It is important to be careful handling the mouse stuff. Scoop and brush out while outside and wearing an N95 mask. Wipe as much as possible with 70% Isopropanol, a 1/10 dilution of household bleach or disinfectant cloths, keeping wet those parts that won't be damaged by it, and the interior of the cabinet. The reason for this treatment is to kill off the diseases that mice carry, including "hantavirus". At worse, hantavirus can get you very sick. At best, if you contract and recover from hantavirus, the antibodies will affect certain immunochemistry lab tests, such as tests for therapeutic drug levels that are run on those being treated with digoxin, certain anticonvulsives and certain antibiotics. (Sorry, my previous career as a Lab Tech and Apps Specialist for a BioMed kicked in).

This set uses a "Reflex RF / Audio stage", hence the plate of the first tube going through the primary of an RF and AF transformer. This stage and the Audio Output stage are both supplied by the "B+". The detector is supplied by the +22V "Detector B+. This is similar to my FADA 160, but the 160 is a 4 tube job.

The 2nd tube in the set is a grid leak detector. Per the RCA Receiving tube Manual (Version RC10, 1930), for the grid leak resistor (R16 on your schematic), any resistance between 1 and 5 megohm will work. The higher the resistance the greater the sensitivity. the lower the resistance, the less the distortion and instability. 2 megohm is common. The cap should be 250 pF (0.00025uF). Considering the open frame of the cap, replacement (under the chassis or whatever) may be the best alternative. I say this merely because of the possibility of leakage with an unsealed cap. this cap can also suffer from SMD. I did have one of these short. Heck, that cap is 100 years old.

Now for my $0.02 on the "jumper wire". At 45V on the RF/1st AF and 2nd AF plates, bias is not really needed, however at 90V, the -4.5V bias was needed. It is possible that a radio technician (if an "NRI man", a "Radiotrician") added the jumper permanently to prevent miswiring by the customer, or maybe Crosley installed the jumper, and the instructions to the installer were to cut the jumper if 90V B Battery and 4.5V C Battery were used.

As for a speaker, the sound would be weak (a 01A puts about 0.010W at 90V), but for your purposes, a speaker and output transformer from an AA5 will get you going till you get working headphones or horn. if you have a 112A, that will get you a little more miliwattage. You can also hook up an amp to the secondary of the transformer.

Hope this all helps.

[radiorich]

Hello Mr Fixr,
Yes you never can be to careful with mice damage .

Well Bob you sure do some beautiul work !

Sincerely Richard

[klondike98]

Thanks guys. No, I'm no expert. My only real background in electronics came in grad school (Chemistry) from an early edition of "Electronics and Instrumentation for Scientists" which at the time involved mostly learning about digital AND/NAND/NOR/OR gates, OpAmps, and basic electrical stuff like V=IR.

I have had terrific help from a number of Phorum members in learning all the things that go into restoration and am still learning...that's what's fun about it all, learning new things and seeing these old radios come back to life. Yep, had an N95 mask on while cleaning and will do a bit more disinfecting as well. Appreciate the help on the 2meg resistor and thoughts on that jumper wire. I have an ARBE III power supply so I'll hook up the 90v and a C- from that without the jumper wire in place.

[Chas]

Might make a resistance check with a VOM of the two audio transformers, looking for values up to about 300 to 1k on primary and from 1 to 2 k on secondary. If the coil(s) are open check the internal leads, sometimes a repair can be made.

The coils can be replaced with windings from ARBE-III, these have the high resistance required to properly load the driving plate circuit. If low resistance windings are used results may be problematic.

Polarity of the coils is important in a reflex, so if using replacement windings with a tap start of the winding needs to be found so the set will not oscillate. If there is an oscillation from transformer replacement re-open one of the transformers and reverse a pair of connections.

If the detector grid capacitor is leaking so long as it is higher than 10 megs the cap can still be used as the sum of the grid leak resistor would apply. FWIS it is a Dublier 601 with leak clips and lugs.

Fair warning, almost ALL of the insulating parts in this Crosley are made of a "MUD" material. This is a thermoforming compound of coal, barytes and shellac. It will melt and flow at soldering temperature. Its surface can be marred by cleaning with thinners, alcohol, and detergents. It is brittle, the key in the tube sockets is known to break away...

I would use the "C" supply from the ARBE..

Do not starve the tubes! The "A" battery is 6 volts not 5 volts...

GL

Chas

[Radioroslyn]

Hey Bob, Here's some ancillary notes about the Trirdyne.

https://philcoradio.com/phorum/showthread.php?tid=7614

GL

[klondike98]

Thanks Chas, the audio coils all ohmed out OK. The capacitors were "open" when checking with an ohm meter, but I don't have a capcitor tester that measures for leakage at higher voltages. The multimeter capacitance measurement was nominally OK although they are at the low end for measurement on that meter. The thermoforming MUD parts are already pretty dull, some from dirt and probably from cleaning. I'll see what I can do to improve its look. I'll also try to add some white paint in the lettering in some places as they are a bit off.

Thanks Terry, I should have known that you would have seen one of these in the past!!

[Chas]

...but I don't have a capacitor tester that measures for leakage at higher voltages.

That is fine on the cap testing with Ohm meter. The Dublier 601's are vacuum impregnated and unless under water or scorched will be fine. Great news on the audio transformers. Modern windings do not use glassine in between the layers the turns are closer together so the added capacitance shunts the higher audio notes.

Recall the MUD parts, re-solder every connection, loosen and re-tighten every electromechanical connection. This is sort of "shotgun" approach, but the mixed metals in both a mechanical and soldered joints do develop a poor connection after some 98 years.

Some of the sheen on the mud parts can be restored by using a modified French Polishing approach using boiled linseed oil rubbed in. Be sure to properly dispose of linseed soaked rags they will spontaneously combust.

Seal the parts (the linseed) to restore the intaglio first, then look to Markal 80220- Paintstik Original B Solid Paint Marker for Oily, Icy, Wet, Dry or Cold Surfaces, Weather- and UV-Resistant, White Color, This product ages in a few weeks to a light wheat color rather than a stark white color. The act of sealing prevents the colorant from creating a whitish haze in the area of application...

GL

Chas

[GarySP]

My AK 20 Big Box has a very similar grid leak resistor, but mine is a glass tube. Found it rattling around in the cabinet when I got it. Take care and BE HEALTHY! Gary

[MrFixr55]

That is the 2nd time I have heard of "Thermoforming". The first time was with the socket assembly of my GE RCA Radiola II. The stuff appears to be able to distort under normal to slightly high (attic?) temperatures, as many of these socket assemblies in the Radiola II are warped. and collectors actually recommend removng or "unlocking" the tubes. (Mine is fairly straight.)

[klondike98]

Finally got back to working on this set. Further cleaning of the chassis and cabinet took place along with resoldering some connections. I found and used a different paint stick than the one you suggested Chas, we'll see what happens over time but good enough for now.
[Image: https://www.dropbox.com/scl/fi/95cvjoa95...b5df&raw=1]

The lacquer on the set was easy to scrape off rather than try to use solvents or paint stripper.
[Image: https://www.dropbox.com/scl/fi/oe6appqpf...k58s&raw=1]

Hooking the chassis up to the ARBE-III power supply I used B+ 90v, B+ 22v, A+ 6v, A- and C+ connected together and C- at -4.5v and B- connected to A+ (used the ARBE-III documentation for the way to set up the ARBE-III). With my SSTRAN transmitter powered up I was able to tune in the hits listenting to it with a headset!
[Image: https://www.dropbox.com/scl/fi/zv5fijmwz...7dmm&raw=1]

...and finally the set all back together (at least until I get the horn speaker repaired and working to see if the final audio section is working).

[Image: https://www.dropbox.com/scl/fi/x83f9e0gb...y6fo&raw=1]
[Image: https://www.dropbox.com/scl/fi/euuq1yaz1...0hy0&raw=1]

[GarySP]

Nice work, Bob. Take care and BE HEALTHY! Gary

[MrFixr55]

Another SWEET Bob's Restoration.  Really nice job!!

[klondike98]

Thanks guys. That was fun. It’s the oldest set I have worked on so I learned some new things thanks to help from this Phorum. What a pain it must have been to deal with those batteries. The 1123 version of this set had a larger cabinet so that you could put the batteries inside it.