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  1. S

    Need help with a President Grant (Export model)

    The HG-2SC2312 have arrived. hFE of 47 and 51, quite well matched. @ DoctorAudio: it was a good tip to get these(y). I replaced both finals and set the bias to 40mA for each (50mA for the driver TR43 according to the manual). I re-did the Tx alignment and now the amplitudes of the RF...
  2. S

    Need help with a President Grant (Export model)

    Sure I will. They should get delivered in a week or so. I will report here.
  3. S

    Need help with a President Grant (Export model)

    Not at all! It was little work and the right thing to do to check the output tank circuit first. Besides, I am learning a lot :cool:! Thx for the warning - good that I haven't ordered yet those 2SC2312 on eBay. I am going to try get a pair of HG-2SC2312...
  4. S

    Need help with a President Grant (Export model)

    I did not have the stomach for doing it with the hemostats:sneaky: so I did the test with the base and collectors disconnected. With only TR41 disconnected the voltage on the dummy load measures 36V p-p With only TR42 disconnected the voltage on the dummy load drops to 2V p-p! Testing the two...
  5. S

    Need help with a President Grant (Export model)

    I do not have a very accurate Wattmeter for 27MHz, I only have an Albrecht SWR-30. So I am measuring the amplitude of the voltage Vpp on the 50ohm dummy load with the oscilloscope, 10x probe, then I calculate Power= [(Vpp/2)*0.7071]^2/50 With 52.5V p-p on the dummy, corresponding to 6.9W...
  6. S

    Need help with a President Grant (Export model)

    I removed and measured C176 and C186, they are good (reading 70p and 151p respectively). I put back C177 and C183 but not C184; but there is no improvement - still only 46.5V p-p on the dummy load (Tx AM unmodulated). It reaches 52.5V p-p with VR13 (AM Carrier power) all the way up...
  7. S

    Need help with a President Grant (Export model)

    Many thanks for the advice! I removed the caps, tested them for leak at 100V DC and checked the values. C183 (nominal: 560pF) reads 600pF C184 (nominal: 47pF) reads 74pF (in fact the cap installed was 68pF) C177 (nominal: 150pF) reads 155pF So I guess the next step would be (1) to put back...
  8. S

    Need help with a President Grant (Export model)

    Hi everyone! (Hope this is the right place to post this ;-) I got hold of a President Grant - Export model, chassis PC-999AD, in very good state. I completed the whole alignment following the service manual at this link (the schematic is the one at p 26). All is fine with the radio - with one...
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