[BC] WGUN Westinghouse

[Bob Groome]

Dick

Doc Massomian in NYC had a composite 10 kW using
892R's for PA and Modulatiors. I bought his Mod
xfmr and reactor in the 70" to repair a BTA-5F.
His MOD xmfr weight over 2,000 Lbs. and reactor
wasn't much smaller! I think a copy of his
original schematic may still be at WERE in
Cleveland. I needed the info to file for
composite on my modified RCA. Which could do 125%
Positive (actually more, but we can't talk about
that), THD was less than 1% from 25 to 12000 Hz
(back when we could go that high) and the IM was
around 5%, as I recall. 3dB points were 22 Hz and
15 kHz. It was really all about the mod iron.

Bob
--- "Johnson, Richard" <rjohnson at analogic.com>
wrote:

> 
> On Wed, 28 Mar 2007, Scott Fybush wrote:
> 
> > Bob Groome wrote:
> >> So did KMOX, WWWE(WKYC-WTAM) and WHAM
> >>
> >> I've seen them but don't think any of the
> are
> >> functional. Not sure any of them are even
> still
> >> ther.
> >>
> >> Bob
> >
> > I was just talking to the WTAM guys this
> morning...would have asked
> > about their Westinghouse if I'd known!
> >
> > WHAM's Westinghouse was removed a few years
> ago when they put in a DX50.
> > (Sadly, I never got to see it!)
> >
> > There was one at KEX until a few years ago,
> too, but it's gone now.
> >
> > The only functioning HG I've seen in recent
> years is at WOWO.
> >
> >
>
http://www.oldradio.com/archives/stations/ccs/wowopix.htm
> > http://www.fybush.com/site-021128.html
> 
> 
> The most impressive AM Radio installation I
> ever saw was a
> mere 10 kilowatt. However, it was a
> "composite," read home-
> brew rig at radio station WTYM in East
> Longmeadow, MA. Its
> call letters have changed to WNHP and it now
> runs only 3 kW,
> while it used to run 10 kW on 1600 kHz.
> 
> The transmitter was built into the basement of
> the building.
> It consisted of four screened-off areas in
> which timber framing
> was covered with "rabbit-wire." The screened
> areas were for
> the final amplifiers and drivers, the
> modulators and drivers,
> the RF exciter, and the audio exciter. The HV
> power supply was
> in the open as were the modulator components.
> 
> The final amplifier tubes and the modulator
> tubes were all
> of the same type (unknown) and were nearly as
> tall as a man
> with a grid connection on the side and a plate
> connection on
> the top. The filaments of these tubes were
> supplied by
> four separate motor-generators as was the bias
> supply.
> 
> Both the modulators and the RF finals were
> push-pull triodes.
> The RF finals used crossover neutralizing
> capacitors that
> were large cylinders. The output used fixed
> capacitors with
> variometer tuning plus a gigantic
> counter-balanced swinging-
> link for output loading. The grid circuit,
> which was the
> plate circuit of the preceeding stage (also
> triodes) had
> the largest air-variable capacitor I ever saw.
> It was the
> size of an automobile! I have seen many
> transmitters including
> gigantic Western Electric machines. This little
> 10 kW rig
> was the largest I have ever seen. It was truly
> impressive --
> plus it was a beautiful work or art.
> 
> Earl Hewinson was the Chief Engineer and he
> would upgrade
> it periodically to use the "latest technology."
> For instance,
> the RF exciter used a pressure-mounted crystal
> in a
> thermostatically controlled wooden box. It was
> maintained
> at 60 degC using a thermometer that contained
> some contacts
> that would open if the temperature got too
> cold. This
> reverse sensing was accommodated using a relay
> that made
> a loud noise. Even in the studio above, one
> could occasionally
> hear the clicks of that relay. When I completed
> the Type-
> Acceptance of my transmitter I built at WDEW
> (read my book),
> Earl asked me to make a crystal oscillator
> substitute for
> his wooden box. I made one, using one of those
> "new fangled"
> AT cut vacuum-mounted crystals invented by
> Northern
> Engineering, just like I used in my
> transmitter. The
> oscillator was a 12BY7 with the same as an
> untuned buffer.
> This was normally used as a TV video amplifier.
> Its low feedback
> capacity made it ideal for the application. The
> buffer fed a
> 6146 for Earl's transmitter. These were the
> first "modern"
> tubes to go into that rig! Earl got the station
> manager
> to pay me $50.00 for the design. That was not
> too bad for
> one day's work of an eighteen year old! That's
> about the
> same as $500.00 nowadays. I made lots of money
> with a
> Greenlee punch!
> 
> Cheers,
> 
> Richard B. Johnson
> Project Engineer
> Analogic Corporation
> 
> 
>
****************************************************************
> The information transmitted in this message is
> confidential and may be privileged.  Any
> review, retransmission, dissemination, or other
> use of this information by persons or entities
> other than the intended recipient is
> prohibited.  If you are not the intended
> recipient, please notify Analogic Corporation
> immediately - by replying to this message or by
> sending an email to DeliveryErrors at analogic.com
> - and destroy all copies of this information,
> including any attachments, without reading or
> disclosing them.
> 
> Thank you.
> _______________________________________________
> 
> The BROADCAST [BC] list is sponsored by
> SystemsStore On-Line Sales
> Cable-Connectors-Blocks-Racks-Wire
> Management-Test Gear-Tools and More!
> www.SystemsStore.com       Tel: 407-656-3719   
> Sales at SystemsStore.com
> 
> 


Bob Groome 
The only statistics you can trust are those you falsified yourself.                                         Winston Churchill

Home address is bobgroome at yahoo.com
Work Email is bgroome at eriinc.com
Web site is http://www.bobgroome.com
Cell Phone  (916) 705-0040
Electronics Research, INC (ERI) Work Phone (916) 681-4969
Fax (413) 683-6907


 
____________________________________________________________________________________
Get your own web address.  
Have a HUGE year through Yahoo! Small Business.
http://smallbusiness.yahoo.com/domains/?p=BESTDEAL