[AMPS] Caveat on Dentron Filaments + MLA-2500B Notes

[Tom Rauch]

> The coil in the "B" model measures 19 uh...very adequate for a Q of
> 10-12 on 160m. (1100 ohms plate load)

Sounds high from what I remember. Was that measured in place, 
with the top on? 

> > 2.) Add a swamping resistor on the input
> 
> You don't have to....a 100 ohm swamping resistor is standard,
> unless some "HFer" has cut it loose!

The swamping resistors I remember are fairly inductive. They 
mostly disappear on ten meters, even if they are there. 

> > 3.) Check the bleeders. Dentron used carbon (an absolute no-no)
> > resistors and sized them, in some models, so the 2 watt resistor
> > dissipated 2.2 watts. Bleeders always should be metal, not carbon.
> 
> This must be a late "B" model I have...it has 120k ohm MOF's in it.

Or it was fixed.
> 
> Denny used two 1 ohm 1 watt resistors in parallel at the
> base of the plate choke.

1/2 ohm is not a glitch resistor. It is only useful as an indicator that 
shows when the tubes are bad. 


73, Tom W8JI
w8ji@contesting.com

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