[Hallicrafters] TO Keyer

[Roy Morgan]

At 09:22 AM 9/22/03 -0400, you wrote:
>Hello all !
>
>I am fighting with 2 TO keyers...both are missing some "dits". I have 
>replaced the relays, the tubes, and some caps. But they still do it.
>
>I have also used 3 different paddles to eliminate a possible paddle problem.
>
>If anyone has experienced and corrected this, I sure would like to hear 
>from you !


Bob,

1) Measure all high value carbon resistors. You will, repeat will, find 
many have drifted high in value.  Replace as needed.  Carbon film or any 
other thing will be FINE.

2) Replace all, repeat all, paper caps. Do not fail to replace ALL of them. 
Any, repeat any, modern film cap of the same value will be fine.

3) The mercury relay must be upright to work right. Having it on its side 
may make it fail to work.

I have some T/O keyers here and will be happy to hear how you make out and 
what it was that caused it to drop dits.

Oh: if you can get 5963's (I think that's the tube number) to use instead 
of 12AU7's, they may avoid trouble over time.. they are computer rated with 
special cathode composition that avoids "cathode interface" problems.

(The manual is on BAMA.)

Roy


- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
7130 Panorama Drive, Derwood MD 20855
Home: 301-330-8828 Work: Voice: 301-975-3254,  Fax: 301-948-6213
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