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Title: VIKING2 R30 CLAMP ADJUSTMENT.. Post by: ve6pg on April 14, 2009, 12:21:07 PM ..hi from tim...'been werking on my viker, and was wondering the procedure for adjustments to the chassis mount pot. i believe it to be, R30, 1MEG...ideas?
..sk.. Title: Re: VIKING2 R30 CLAMP ADJUSTMENT.. Post by: W7SOE on April 14, 2009, 12:53:08 PM Hi Tim,
That is the clamper tube adjustment as described in the manual: http://bama.edebris.com/manuals/johnson/viking2/ Making that adjustment involves adjusting r13 a ww adjustable resistor, be careful s the windings are fragile and may be tired from many years of HOT operation. 73 Rich Title: Re: VIKING2 R30 CLAMP ADJUSTMENT.. Post by: ve6pg on April 23, 2009, 01:51:44 PM ..ok...i adjusted the resistor for modulation resting current...but now, during a transmission, the resting current is slowly rising....i keep any transmissions short, fer this reason...any ideas of the current increasing?..
..sk.. Title: Re: VIKING2 R30 CLAMP ADJUSTMENT.. Post by: W7SOE on April 23, 2009, 03:25:14 PM Hmm, kinda sounds like a cap going bad. Have you replaced all the paper caps?
At first glance you might want to check C8, bypass cap connected to the 807 grids...... Rich Title: Re: VIKING2 R30 CLAMP ADJUSTMENT.. Post by: W1AEX on April 23, 2009, 03:26:02 PM How good is the 6AQ5 clamp tube? If it's weak, that will cause the screen voltage to wander under load. That would be my best guess. Check the components around that little voltage divider at the ouput of the 6AL5 bias rectifier too. AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
Rob W1AEX |