Amps
[Top] [All Lists]

[AMPS] low out on 10m--clarification

To: <amps@contesting.com>
Subject: [AMPS] low out on 10m--clarification
From: nx7u@primenet.com (Scott Townley)
Date: Thu, 21 May 1998 17:24:47
At 11:55 21.05.1998 EDT, km1h@juno.com wrote:
>
>On Wed, 20 May 1998 17:13:55 Scott Townley <nx7u@primenet.com> writes:
>>Clarification:  Low out on 10m is ALSO low DC in on 10...plate voltage
>>nominal but Ib quite a bit low.  Maybe this is typical of low output 
>>on
>>10m, but in case that's the key indicator...
>
>Low DC in???  Or do you mean RF??
>If the input network has a high VSWR to the exciter or is just a poor
>design the output will suffer. 
>An old clunky WW2 mica .01 type coupling cap to the filaments could also
>be quite lossy at 10M, etc.
>
>73  Carl  KM1H
>

No, just low DC in.  The particulars:
Eb=2600W        typ. Eb=2500V
Ib=440mA        typ. Eb=630mA
Pdc=1140        typ. Pdc=1550W
Po=590          typ. Po=1000W+ (I only have a 1000H slug)
Pin=90W for rated grid current Ic=240mA.

Coupling caps to filaments are ceramic disc .01uF

I wish I had an HV o'scope probe so I could see if I was swinging the plate
voltage enough.
It behaves as if there's additional RF resistance in the output circuit
somewhere...but the tank is a B&W850 and the RFC B&W800, so the components
shouldn't be suspect (right?)

------------
Scott Townley           
nx7u@primenet.com
------------
Collector of:
        Stoddard Aircraft EMI/RFI receivers and accessories
        Big Parts for that Big Linear Amp 
        70's era RF test equipment HP/GR/Tek
        Radio-related technical reference material 1940+
        ...anything else that will keep me off the streets at night

--
FAQ on WWW:               http://www.contesting.com/ampfaq.html
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm

<Prev in Thread] Current Thread [Next in Thread>