[ARC5] [Milsurplus] ARB parts

[David Stinson]

From: Hubert Miller
Subject: Re: [Milsurplus] ARB parts

>.I still toy with the idea of putting the ARB + ATB set together. 

 

Reviving and ATB is not for the timid, especially the tuning units,

which are often bad and difficult to service.  They seem to have

built them "from the inside, out" and the ceramic coil forms 

are fragile.   The contact springs inside the transmitter which

engage the tuning units are subject to metal fatigue and are

often broken-off.   Getting that channel-switch kludge out to

service requires extensive dismantling of the transmitter.

  I was able to form a couple of gold-plated relay contacts

and solder them in place for the "B" channel to make contact

without  the disassembly,  but I had to stand on my head to do it.  

When I retire (ha ha that's a laugh), I'm hoping to take the 

month needed to go back and "do it right."  Why the "B" 

channel?  Because for some reason I cannot know, RCA

decided that Channel "A" requires the  Rube Goldberg

switch to be energized and "B" does not.

Once going it is a cool set- has that 1930s, "Steampunk" look.

Good audio, too.

 

P.S. Never burnish any relay or sliding contact in a ATB

with anything abrasive- Brown paper wetted with DeOxIt

is about as strong as you want.  The contacts are coated

with an atoms-thick layer of Iridium.  Even a mild burnishing

will destroy this layer.  

 

73 Dave AB5S

 

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