[Amps] input tuning

[Roger (sub1)]

On 6/21/2011 12:45 AM, Carey Lockhart, KC5GTT wrote:
> Hello guys,
>
> working on another gs-35 amplifier for 2 meters. i have noticed that all of the tubes i have had have been different. that is to say not one tuned input circuit has been the same. working on this one tonight i have noticed when i touch the screw driver to the trimmer cap the input swr goes flat. remove the screw driver and it has about 1.2 swr. which comes to about 200w of output difference. these tubes seem to be very touchy. so what am i seeing. not enough capacitance? righ now i have the screwdriver just laying in the hole with a nylon spacer keeping it from ground and the input is perfect.

Use a tuning wand instead of a screwdriver.  Lost of rigs are very 
difficult to tune using metal screwdrivers.

73

Roger (K8RI)