[Johnson] Want Ranger pwr xfmr

[Dee C. Almquist]

I suggest Heyboer Transformers. Their quality is excellent & so are their
prices. http://Heyboertransformers.com
73 es Dee


----- Original Message -----
From: "John Lawson" <jpl15 at panix.com>
To: <johnson at mailman.qth.net>
Cc: <amradio at mailman.qth.net>
Sent: Friday, November 25, 2005 12:36 PM
Subject: [Johnson] Want Ranger pwr xfmr


>
>
>    Anyone happen to have a NOS or Good-Used Ranger power transformer for
> sale?  I need one - or a Good-Used Ranger - or, a new hobby... ;}
>
>
>     After several hours on the bench last night - it is apparent why this
> old girl was shelved - it came to me with a 5R4 in the HV socket, but the
> fils didn't light, tho the tube was good. So sure enough - someone had
> tied the 5V fil lines back, and there was a 10-ohm 10W resistor in series
> with the B+ lead.
>
>    I made a plug-in SS rectifier, installed it, switched the rig on - and
> blew both diodes and both line fuses to little bits.
>
>    Ok.
>
>    So I restored the original circuit - there is a definite 'under-load'
> short from the HV rect fils to the HV winding.
>
>    Ok..
>
>   Disconnected all that - the LV side works fine, Osc runs, buffer runs -
> can 'zero-beat' to a receiver, frequency of VFO seems accurate.
>
>   Ok...
>
>   Tansformer voltage and resistance checks are within 10% of spec.
>
> Ok....
>
> Put new diodes in put a Variac and ac ammeter in the mains line, turned it
> up slowly - POW.  Actually, with the diodes in cicuit, it appears to the
> Variac / AC Ammeter that the power transformer has a dead short. Having
> replaced the filter caps, and checked the plate choke - it ain't them. The
> B+ line resistance is slightly over 20K.
>
> Ok.......!
>
>    In this process the power transformer has begun to get slighly warm, so
> I went back to checking the LV side - as I was testing, the transformer
> started to arc internally - and resistance measurements now show the
> fil-to-HV short.  So: It's toast.
>
>
>    While working on it, I did get to listen to a wonderful, hours-long AM
> QSO on 3.885 - altogether seven or eight stations from both coasts and the
> midwest - nice loud sigs, band wide open and quiet - little QRN and no QRM
> (for once)
>
>
> NOW: Today I'll try and get the Valiant healthy.
>
>
>     What else are 4-day weekends for???
>
>
> Cheers
>
> John  KB6SCO
>
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