I would expect to find that the input band switch has "slipped" relative to
the output band switch. Carefully check the alignment of the band
switches. Also be sure that the bandswitch corresponds correctly to the
front panel..
73 and good luck
Jim W7RY
-----Original Message-----
From: bob alexander <realex@flash.net>
To: amps@contesting.com <amps@contesting.com>
To: <amps@contesting.com>
Date: Thursday, December 24, 1998 3:51 PM
Subject: [AMPS] SB-200 problem
>
>Howdy,
>I've been troubleshooting an SB200 and have gotten exactly
>nowhere. Measured operating conditions are:
>
>Plate voltage = 2100 indicated on front panel meter
>(I've measured 350 VDC +/- 10% across each filter cap)
>there is continuity between p.s. and plates (no open choke)
>
>Bias (measured between grid and cathode) = -125 VDC in standby,
> -2 VDC keyed
>
>Idle current = 20 Ma indicated
>
>Plate current = 100 Ma with 100 Watts drive
>
>Power output = 100 Watts max on any band
>
>Input VSWR between 2 and 3:1 depending on band
>
>Filament voltage = 6.31 VAC (center tap is grounded)
>
>All components check O.K.
>
>I get the same results with a second set of 572Bs
>
>Does anyone have any suggestions?
>73, and Thanks
>Bob, W5AH
>
>--
>FAQ on WWW: http://www.contesting.com/ampfaq.html
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>
--
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