24-03-2018, 03:05 PM
Lou,
Re-reading your initial posting, you mention the trimpot works OK. What trimpot??? There is no trimpot in my 50D element. Its circuit diagram is as shown in the accompanying schematic. The terminating resistor "R" measures as 75 ohms. It in inside a small sleeve that forms an adjustable, shunt compensating capacitor. Resistor labelled "82" is 18.4k.
I suppose calibration is performed by carefully adjusting the coupling of the auxiliary arm in the slug.
Chas
VK3PY
Re-reading your initial posting, you mention the trimpot works OK. What trimpot??? There is no trimpot in my 50D element. Its circuit diagram is as shown in the accompanying schematic. The terminating resistor "R" measures as 75 ohms. It in inside a small sleeve that forms an adjustable, shunt compensating capacitor. Resistor labelled "82" is 18.4k.
I suppose calibration is performed by carefully adjusting the coupling of the auxiliary arm in the slug.
Chas
VK3PY