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Mike Osc AM radio transmitter?
#8

Here are a couple shots of the finished recap. I added a 1a fuse in case the diode shorts. After a couple of tries with different dropping resistors, I settled on a 100 ohm 10w. Runs barely warm. This put my B+ at 95v and the voltage across both tubes filament at 2.8v at 120v line. The tube filaments are connected in series. 

Test 1: I found it set right around 1600 kc. The input was too sensitive for a line input and was over modulating. I put a 100 ohm resistor to cut down the signal. I may have to adjust some. Sound is clear, but very tinny. I am going to play around some with the input coupling cap and see if a different value will up the quality. As far as range, it doesn't go much past the radio room. Need to clean some dirty tube socket contacts and tighten up the input jack. 

If anyone can read the color code on those brown ceramic capacitors, it would be great. My cap tester has them at 150pf. I am about half color blind. 
   
   

If I could find the place called "Somewhere", I could find "Anything" Icon_confused

Tim

Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44


Messages In This Thread
Mike Osc AM radio transmitter? - by TV MAN - 01-29-2018, 06:57 PM
RE: Mike Osc AM radio transmitter? - by Arran - 01-30-2018, 05:52 AM
RE: Mike Osc AM radio transmitter? - by David - 02-01-2018, 10:29 AM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-01-2018, 04:03 PM
RE: Mike Osc AM radio transmitter? - by Arran - 02-01-2018, 11:04 PM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-15-2018, 12:35 PM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-15-2018, 12:55 PM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-15-2018, 11:43 PM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-17-2018, 07:37 PM
RE: Mike Osc AM radio transmitter? - by 35Z5 - 02-23-2018, 12:03 PM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-23-2018, 08:37 PM
RE: Mike Osc AM radio transmitter? - by 35Z5 - 02-23-2018, 10:28 PM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-24-2018, 03:05 PM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-24-2018, 07:01 PM



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Good picture, When was it taken? You don't look in it like a guy who has a teenage son :)morzh — 06:13 PM
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Love the pic! I'm southern IL, so wouldn't be much help and Bob Anderson is very good on those, but lives in Chicago are...TV MAN — 05:25 PM
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You're correct. I was misinterpreting the key position. I now know where it is, and things are making sense. I appreciat...bluecap — 04:29 PM
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