[AMRadio] Simpson 260

[Bill Guyger]

FWIW in a continued answer to the comment the other day about why anyone would want to use such old tech. GatesAir / Harris states in the service manual for their 3DX series transmitters (it's actually in a separate sub manual on the PA modules)that the factory approved method to check the FET's in the PA modules is to use a Simpson 260. 

There are 8 FET's in each of the PA modules and a 50 Kw model has 63 modules. Each module operates as a 3Kw push pull amp that the logic can turn on individually as required by the modulation. All the odd numbered modules are used first with the even numbered being added as required. Except about once an hour when the logic starts using the even numbered modules for about 15 minutes just to be sure they're OK, then the odd numbers go back to being the primary.

Bill AD5OL

Sent from my iPhone

> On Jul 27, 2018, at 8:36 PM, Rob Atkinson <ranchorobbo at gmail.com> wrote:
> 
> Two other good analog VOMs:
> 
> The military ME-9 B/U made by Phaostron in Pasadena Calif.
> 
> and the Triplett model 625N
> 
> The  Phaostron is so well made but bigger and heavier.  Its only
> negative is that its meter face is a bit on the small side compared to
> the Simpson and Triplett which are easier to stand up on end and use.
> 
> 73
> 
> Rob
> K5UJ
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