[TMC] RE: [AMSWAP] TMC item

[H.L.]

John:

No problem about the delay. Non-ham activities have slowed me down the last two months, and I still am not finished building the control unit for my SBE/GPE/PAL system.

I don't think the power supply you obtained is an SBE power supply or is strong enough to power an SBE.  Your transformers are all "TF-105" models, and your 700V CT HV transformer is rated at only 125 mA. I don't know what TMC units these transformers were part of.

The SBE-2 manual parts list is as follows:

T401 (part # TF161)  power transformer (current rating not listed but the schematic shows a 250mA fuse between the HV center tap to ground, so the current rating must be above 250 mA. And, I am guessing that somewhere between 300V-0-300V  to 400V-0-400V is the correct voltage rating for an SBE power transformer.) 

T402 (part # TF104) 6.3V separate filament transformer for an SBE.

Your two chokes (10HY at 200ma.) are the same ratings as those in the SBE schematic although the listed parts are identified as "L401" and "L402" (part # TF144).

73, Hal



>HAL, Good afternoon.  Please pardon the long delay between communications but that is pretty much the fastest mode I have :-) ...
>
>Attached are pictures of the SBE supply I bought from the Arizona list member (see how good my memory is :-) ...  the original supply was on a sled on the side of one of those "all in one" TMC PAL installations.  He had to trace the wiring to the SBE and then fashioned a loose cable which worked.
>
>I've taken pictures of the transformer tops and thought this might help us with the xmfr ID puzzle.  I have already talked to Harbach (who bought Peter Dahl's copyrighted business) and was told that remaking these would be a piece of cake for them.  So my thought is if we can get sure of what the two power xmfrs need to be, perhaps we could add some beef to the current capacity and then get a few others off the list to go in for having some  of these made. 
>
>See if the pictures are helpful and make sense to you.
>
>Best regards,  John
>
>
>----------------------------------------
>> Date: Sun, 22 Jun 2008 12:31:25 -0700
>> To: w5jv at hotmail.com
>> From: hl at sfsu.edu
>> Subject: RE: [AMSWAP] TMC item
>>
>> Hi John:
>> Quick reply on a hot Sunday:
>>
>> My schematic shows:
>>
>> Pin A: 6.3VAC
>> Pin B: 6.3VAC
>> Pin C: 6.3VAC
>> Pin D: 115VAC
>> Pin E: POWER SWITCH S103 and 115VAC
>> Pin F: POWER SWITCH S103
>> Pin G: +150VDC B3 regulated
>> Pin H: +250VDC B1
>> Pin I: +180VDC B2
>> Pin J: +225VDC B4
>> Pin K: no connection
>> Pin L: ground
>> Pin M: no connection
>> Pin N: ground
>>
>> I think the power transformer HV is 350-0-350 VAC. The current must be at least 300 ma because of the 6146 output tube in this 20-tube 1-Watt exciter. Strange!
>> I wonder if a 2E26 or other smaller tube could be substituted without penalty.
>>
>> I am not clear what you mean regarding the relationship between the PAL amplifiers and the SBE exciters.  Don't they always have their own independent power supplies? The on-off and standby functions can be interconnected, but I am new to the world of TMC and do not know what a "doghouse unit" or a "SBE supply inset in a frame." are.
>>
>> I hope the pin connections are helpful.
> > Regards, Hal
>