LinkBack Thread Tools Search this Thread Display Modes
Prev Previous Post   Next Post Next
  #20   Report Post  
Old December 27th 04, 11:42 PM
Chuck Harris
 
Posts: n/a
Default

zeno wrote:
On closer examination again, I do now see a couple of small diodes (both have
the number 205) which were hiding behind some black spaghetti pushed up against
them. This little homebrew seems to have been carefully assembled and I have no
reason to believe that the 6L6 is not the correct tube. The little rig does
work, but, as mentioned, the CW note was quite distorted and unacceptable. How
would one go about trouble shooting this problem. At this point I have limited
bench equipment , but might consider acquiring some. An oscilloscope is high on
the want list. Can you point to a part of the circuit which would result in
this very chirpy and wobbly CW tone. I would have to fire it up again to
remember how best to describe the sound of this signal.

Bill K6TAJ


The very first place to go is to check all of the chassis
grounds. If solder lugs are screwed to the chassis, loosen them and
then retighten them. If the octal tube socket has a ground ring, and metal
ears as many do, loosen its screws, and retighten them. Clean and lube the
wipers of any trimmer caps or air variable tuning caps. Clean up the pins
and socket for the crystal. Next would be any electrolytics in the circuit.
And, of course, any paper capacitors. If there are any "dogbone" resistors,
get rid of them and replace them with "modern" carbon composition resistors.

A lot of faults can be found by just listening to the note on a receiver,
and wiggling stuff around.

-Chuck Harris


 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Need "Original" (1937 era) 6U5 Tuning Eye Tube Mdcalvert Boatanchors 1 April 7th 04 11:06 PM
FA: Homebrew tube transmitter on Ebay GS Boatanchors 0 February 10th 04 04:47 AM
Tube tester query? k3hvg Boatanchors 4 February 2nd 04 01:47 AM
FS: Old tube sockets, 4, 5, 6, 7 pin, Hammurlund, GR, ceramic, phenolic,matching plugs, extenders Al Schapira Boatanchors 0 January 19th 04 10:54 PM
Directional Radio Transmitter Simon Antenna 10 December 14th 03 05:08 AM


All times are GMT +1. The time now is 03:06 AM.

Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2025 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017