Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12, 2025) x

Thread Closed

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



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco P45-6365 Universal Transformer Instruction Manual
Can anyone guide me to where this may be found?GRG — 03:00 PM
54C Complete Teardown/Rebuild
I don't think that I have encountered a 12Z3 before, curious how it uses one of those but includes a #43, which is a 25 ...Arran — 02:17 PM
HiFi (Chifi) tube amp build - but my own design.
It's the other forum. I'm also in DIY, but mostly read there. Honestly, I kinda jumped into this without much thought to...TV MAN — 10:43 AM
Philco 71 Code 125
Hello,  I am in need of a schematic for this radio. Mine has the three separate circular tube shields and a shadow me...dconant — 08:06 AM
Stromberg Carlson 1500 Squeal
And life just keeps getting more complicated.dconant — 07:57 AM
54C Complete Teardown/Rebuild
Hello Roy, here is this one sincerely Richardradiorich — 12:45 AM
54C Complete Teardown/Rebuild
Richard, Had grabbed it already but thank you just the same.  I find myself wanting to find some way to block out the...glyphmon — 12:03 AM
54C Complete Teardown/Rebuild
Hello roy, here is a link to the schematic . Sincerely Richardradiorich — 11:54 PM
54C Complete Teardown/Rebuild
Richard, The Silvertone 2014 also is a transformerless set, so I am incorporating a 1:1 600 ohm audio isolation transfo...glyphmon — 11:37 PM
Preliminary work on wife's Silvertone 2014
Did an alignment today which was interesting.  IF alignment went great, almost all was already spot-on.  Adjusting on th...glyphmon — 11:35 PM

[-]
Who's Online
There are currently 2079 online users. [Complete List]
» 2 Member(s) | 2077 Guest(s)
AvatarAvatar

>