[Amps] Transformers

[kq6i at arrl.net]

Would be interesting to see a picture?

Craig
kq6i 

-----Original Message-----
From: amps-bounces at contesting.com [mailto:amps-bounces at contesting.com] On Behalf Of Harold Mandel
Sent: Tuesday, June 17, 2008 5:47 AM
To: Manfred Mornhinweg; amps at contesting.com
Subject: Re: [Amps] Transformers

The transformer specified for the 4CX15,000A project is a 37.5KVA and weighs 565 pounds, dry.

Hal Mandel
W4HBM 

-----Original Message-----
From: amps-bounces at contesting.com [mailto:amps-bounces at contesting.com]
On Behalf Of Manfred Mornhinweg
Sent: Monday, June 16, 2008 9:29 PM
To: amps at contesting.com
Subject: [Amps] Transformers

Hi Dino,

> I just
> picked up a 3750 KVA transformer from MagCap direct, for a GS35B 
> project.

Wow, that's one big transformer! 3750kVA! That's several times larger than the largest pole mount
distribution transformer I have ever seen! 
Did you really mean such high power? I wouldn't believe it!

> There are a number of companies making HV transformers. 

I can't speak for the USA in this matter, but here in Chile there are several companies that make
transformers to order, with quality varying from cheap to professional. Also there are very many small
winding shops, in almost every medium or larger city, which will gladly wind transformers to the specs
of the client. So I would suppose that in the USA, much more developed than my country, there must
exist many more transformer winding businesses than just Peter Dahl. I would suspect that in any US
city of any significant size it should be possible to find a winding shop that will make a pretty
decent transformer for a high power amplifier.

Anyway, I will keep preaching for the do-it-yourself approach. Winding transformers is easy! No
significant machinery is required. I really think that anyone who can build an RF power amplifier,
certainly can wind the transformer for it.

A few days ago I wound two large high voltage transformers for use with my water turbine setup. Today
I published a set of photos showing the construction process of these transformers. Those of you who
are interested can have a look at this page. The transformer photos are down near the end of this long
page:

http://ludens.cl/paradise/turbine/turbine.html

If anyone wants my Excel spreadsheat to calculate transformers, I will be glad to send it by direct
e-mail. This spreadsheat will not do the full job, but it's a significant help in designing and
optimizing transformers.

Manfred.