UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

crestavega · 21st Sep 2016, 10:44 pm

Thanks, I now have something to chew on.
My "dummy load" is/was simply a length of wire which is not really ideal, postponing further investigation pending arrival of a decent dummy load and a bit of reading-up on valve PA's.
I have some familiarity with valve Rx but none with power Tx circuits
can anyone recomend any particular books on the area?

Indeed the vague idea was to get it running on top band, though it is not entirely suitable for ham operation with channelised freqs only and of course no LSB. it is a fairly good aesthetic example, ex coastal MFV, with very little corrosion & all mechanicals working perfectly. I have its partner R105 operational separately.

Excuse my ignorance, but why is it still critical to tune the aerial cct if I have a good dummy connected? I thought the purpose of a dummy load was that it will quietly absorb anything that the output produces (I do appreciate that a dummy load will not of itself stop a wonky amplifier from oscillating)

Reading through the tuning procedure for adding channels is enough to make me sweat. It certainly makes one appreciate the VFO and ATU.

21st Sep 2016, 10:44 pm	#4
crestavega Pentode Join Date: Apr 2014 Location: Kirkwall, Orkney, UK. Posts: 165	Re: SP / Sailor T128 problems - valve help please Thanks, I now have something to chew on. My "dummy load" is/was simply a length of wire which is not really ideal, postponing further investigation pending arrival of a decent dummy load and a bit of reading-up on valve PA's. I have some familiarity with valve Rx but none with power Tx circuits can anyone recomend any particular books on the area? Indeed the vague idea was to get it running on top band, though it is not entirely suitable for ham operation with channelised freqs only and of course no LSB. it is a fairly good aesthetic example, ex coastal MFV, with very little corrosion & all mechanicals working perfectly. I have its partner R105 operational separately. Excuse my ignorance, but why is it still critical to tune the aerial cct if I have a good dummy connected? I thought the purpose of a dummy load was that it will quietly absorb anything that the output produces (I do appreciate that a dummy load will not of itself stop a wonky amplifier from oscillating) Reading through the tuning procedure for adding channels is enough to make me sweat. It certainly makes one appreciate the VFO and ATU.