[AMRadio] Bauer transformer needed

Jim Wilhite w5jo at brightok.net
Wed Jan 29 23:35:28 EST 2014

That transformer sounds like a very good candidate for rewind using quality 
components.  I don't think I would trust an original and the Bauer is too 
nice to scrap.


-----Original Message----- 

I have a Sparta 701 (it was not in good enough shape to restore) I
have been getting parts from and it also has a bad T5.  I wouldn't be
surprised if it is the same part.  I have heard of other Sparta Bauer
rigs, 701s, 707s, with T5 blown so I have a hunch this was a common
failure for some reason.  I'm afraid all I can offer is that on mine,
T5 was supplied by Quality Transformer Co. in San Jose CA and is
Sparta part no. 326-9024 and Quality part no. 1281C.

Here are the winding taps:

Primary:  0 - 208 - 220 - 230 - 240   Lugs 1,2,3,4,5 respectively
Secondary:  9 and 10-- 250 v. 100 ma.   6,7,8-- 870VCT(7 is CT) 125
ma.  15,17-- 6.3v 3A  11,13-- 6.3v 3A

6 and 7 fed a FWB rectifier that was the 800 v. B+ supply for the RF
driver tube, a 6CA7.  This rig ran two 4-500s in the final modulated
by the same.
I see on the 701 schematic the lugs appear to be numbered incorrectly.
This may be why they fried.

Not sure if your part is exactly the same as this but maybe this
information can help you find a substitutes.



On Wed, Jan 29, 2014 at 3:43 PM, Shane Autrey <iam4thapack at yahoo.com> wrote:
> Don K4KYV told me to join the group and see if anyone on this list might 
> be able to help me. Trying to keep it all original/stock before exploring 
> other options. I recently took ownership of a Bauer 707 that has a bad T5 
> L.V./Bias transformer. She was destined for the scrap pile and is in 
> fairly decent shape. The transformer I need is a UTC CG-422. Does anyone 
> have one of these they would be willing to sell to me? Didn't know about 
> this group and am excited to see what takes place over here! I have 
> emailed Bauer and they are trying to find one as well. If all efforts fail 
> I will mount it back up and run some outboard transformers in the chassis.
> Cordially;
> Shane KI4M

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