LinkBack Thread Tools Search this Thread Display Modes
Prev Previous Post   Next Post Next
  #21   Report Post  
Old November 4th 08, 04:06 AM posted to rec.radio.amateur.homebrew
external usenet poster
 
First recorded activity by RadioBanter: Dec 2006
Posts: 224
Default I built a 7.5VAC 21Amp transformer now it has lots of buzz

congrats on the fix..
now you have th epower and the time to contest..
Contesting is much like transformer winding..
Once you learn how to do one turn, you repeat and count until you reach
a goal...
In contesting you do one turn, then another till you reach the time
limit and count your turns.
hi hi
Hank
"raypsi" wrote in message
...
On Oct 25, 12:25 pm, raypsi wrote:
Hey all:

I tore down a transformer I got from ebay it was a Zenith TV power
transformer from days gone by. Re wound it with 17AWG wire on the
secondary and primary. It powers up my 4-1000A filament nicely with
7.25VAC from 120VAC mains. I used a penta-filar winding on the
secondary. Shimmed the bobbin in the core window with some 1/8
thick
virgin teflon. Epoxied the windings to the bobbin. This was a 240VA
transformer and now is a 83watt buzzer / 157watt filament
transformer.

So what is the cheapest I can gits away with sealing these
laminations
from buzzing, I used up all my epoxy sealing the windings.

73

n8zu


I finally got around to clamping the transformer down with grade 8,
1/4inch bolts and nuts That didn't help, luckily I found my 3 hour
epoxy, ran the transformer for 3 hours straight to heat it up, took
the bolts out and with a putty knife slapped on some microwave heated
epoxy on the lams. That took the buzz down to below the level of the
fan noise. In dead silence you can still hear it. Nowhere can you feel
the buzz.

73

n8zu


 
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
WTB: 1000 VCT 6/5VAC XFORMER Smokey[_2_] Boatanchors 1 August 2nd 07 12:22 AM
What to do with lots of receivers and lots of antennas? Mark Shortwave 11 July 17th 04 07:37 AM
Chicago Transformer Mod Transformer CMS-1 Specs wanted Yardleyite Boatanchors 3 April 7th 04 03:03 AM
SX-190 buzz in audio Mark Rehorst Boatanchors 51 November 4th 03 04:44 AM
SX-190 buzz in audio Mark Rehorst Boatanchors 0 October 31st 03 04:21 AM


All times are GMT +1. The time now is 03:30 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