The lower one will take the signal from the cathode follower and amplify it.
#6SN7 CATHODE FOLLOWER SERIES#
I'm thinking maybe a couple FETs in series with the top one controlling the voltage to the lower one which will provide proper modulation. What I now need is a circuit that will amplify the RF signal and feed it into the around 1K attenuator load and also provide proper modulation. The A-C waveforms have a little issue at the top of the waveform, but I may try and adjust the plate resistance and see if I can clean it up a little without affecting bands D-E.īands F-G will no longer be picked up by this method as they have one oscillator coil separate from the rest. I connected that to the cathode follower using just the 10K resistor and the bias set up by the 4.7 meg resistor. I then had the bright idea to insert a wire in both oscillator coil assemblies. I noticed that with the oscillator operating as intended I could hold my scope probe to the currently selected oscillator coil and get a clean sinewave. I tried the values, but with the higher cathode resistance I could no longer use the attenuator so I thought of this. and modulated envelope it could get complex to do it with out tuned circuits to reshape it. If you are looking for purity (sine wave) output of the R.F. The heathkit has a 1k plate resistor and since the tube has a large ouitput they pad it more than once so the output tube is isolated from the load as well as being a standard common cathode amplifier it is more forgiving as to the load reactance. The right(wrong) load can make it oscillate. Simple cathode followers like eico used are not very stable with reactive loads so they isolate it on the output. It runs similar B+ voltage but much higher current and it is not a cathode follower. It uses a sweep tube in a similar circuit of grid modulation and has a higher output level. If all you need is more out put you might look at heathkit 1g42 gen circuit. The modulation process depends on the tube being non linear to mix the signals. You may find tha gives you the additional level peak to peak as the 6SN7 will bias itself to a highr cathode voltage so therefore more room to swing however the modulation characteristic may change and this is also true of rebiasing the 6SL7. Next pop in the 6Sn7 and do the same this way you will know if your power transformer can handle the extra load. I would check the fillament and B+ outputs of the power transformer and note them unmodded. may work out by subbing a 6SN7 in there and see what you get without changing the circuit yet. I thought about this and if you are trying to get higher output of the R.F. The purity of service type generators isnt all that great but doesnt have to be. I am not sure of the goal you are trying to reach.
0 kommentar(er)
