250 watter REDUX/Gates BC-1T/250

[W9ZSL]

  Hello!  I re-thunked the project and am going with separate power supplies and not use the single one based around the Gates plate iron.  Now I have a question for anyone who is familiar with the BC-1T.  One of the answers I got in my last thread was there may have been a BC-250.  Could that have been converted to run 1KW day and 250 night?  If that is the case and a BC-250 could be up-graded to a BC-1T, I got the original plate iron and filter cap.  

Since then I scored another plate transformer to use for the modulator that will give me about 1200 VDC under load at 300 ma and I have a huge 820VAC with no center tap...perfect for a doubler for the PA.  Problem solved?  Remember it will be at least a 4-125A PA modulated by P-P 811As  I'll keep you posted.   73!

Mike
W9ZSL

[W7TFO]

A Gates 250 ran 810's in the finals and mod sections. 

I touched a 250-T three days ago in LA.  KO6NM is doing a 100-point restoration on it.  It looks identical to a 1-T, but has smaller iron down under and 50-watt sockets on a steel panel instead of that crappy phenolic bar socket job.

It might be possible, but converting one up to 1kW would involve a lot of work, as other than the RF deck on top not much is interchangeable.

More likely they had both transmitters at one time, and one gave up it's parts at some time as spares.  Then again, Gates did a lot of weird things over the years.

The original plate iron for a Gates 250 would be more than enough for both the PA & mod sections using the tubes you want to use.  Maybe try the 'economy' hookup using a bridge and the CT for two + voltages.

A "1", be it a D, F, T, G, or H ran 833's with a power cutback system for either 250 or 500.

73DG

[KB3DKS]

I have the original Gates BC-250T up conversion to 1T manual that I can quote from if that would help anyone. It is not in front of me now though. Have to dig it out of the file cabinet in storage.
Bill

[W3GMS]

Hello!  I re-thunked the project and am going with separate power supplies and not use the single one based around the Gates plate iron.  Now I have a question for anyone who is familiar with the BC-1T.  One of the answers I got in my last thread was there may have been a BC-250.  Could that have been converted to run 1KW day and 250 night?  If that is the case and a BC-250 could be up-graded to a BC-1T, I got the original plate iron and filter cap.  

Since then I scored another plate transformer to use for the modulator that will give me about 1200 VDC under load at 300 ma and I have a huge 820VAC with no center tap...perfect for a doubler for the PA.  Problem solved?  Remember it will be at least a 4-125A PA modulated by P-P 811As  I'll keep you posted.   73!

Mike
W9ZSL

Here are a few pictures of one of my restored Gates 250C1 transmitters. This was from the early 40's.  It would not have been a candidate to upgrade to 1KW.  It was strictly  250W box with no upgrade options.  810's push pull in the final modulated by a pair.  Design wise, the BC-250 was similar but just looked different physically.

Joe, W3GMS

[W7TFO]

A real & rare beauty!

73DG

[Mike/W8BAC]

That's a beauty Joe. Is the dummy load on top part of the original design? Tell us about that. Overall I like the looks of it and it fits the decor nicely. Not often you find a retired BCTX in the living area of the house.

Mike

[WD4TC]

 Hello Joe the 250C-1 Looks great,,Hope you and Martha are well...Tim...WD4TC
   and Yes I DO miss it even more Now !  Good Evening...

[W3GMS]

Thanks Dennis for the comment.  Yep, its a pretty one!  

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Mike,
I have a very understanding wife!  Its in our family room which I call "Studio B".  After all, she did buy me a Johnson Desk KW for Christmas 2 years back!  I think that says it all.  With me if something goes in our living space it needs to be pristine and this one certainly qualifies.  I have collected most of the same period Gates accessories from the early 40's for this transmitter.  They are currently being restored.  I was very fortunate to find the Gates Audio Board from the same period.  Fortunately a member on this site had the manual for the board so now I can finish the restoration.  It will look as good as this restored transmitter when done.  

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Tim,

Great to hear from you!   This is actually my second Gates 250C1.  The one I bought from you even looks better!  Yours which turned into quite the project was spread over 3 years but its absolutely gorgeous.  A good Ham friend that use to own a body shop assisted greatly in that rebuild,  Your old one is for 160 and this one is for 75 and maybe ultimately 40.  They work real well up to 40 meters.  

Shortly after I bought the one from you, a gentleman called me up who lived in New York asking if he could make a copy of my documentation for the Gates 250C-1.  It turned out he had one as well and wanted to restore it.  So I got all the documentation and he was very grateful.  When he got his done, we went up and listened to it and see it operate into a dummy load on the broadcast band.  Well, he was up in age and had some health problems and ultimately passed away.  Since we had many phone calls concerning the restoration, I felt attached to his transmitter!  I called Martha up at work and said, we need to go up to NY and buy Frank's 250C-1 since he had passed.  Her comment was, the truck is full of gas so what are we waiting for!  

So that's how I ended up with 2 of these babies!   I never intended to get a second one, but things happen!  

73,

Joe, W3GMS  
      

[W9ZSL]

Well, the station here (WOBT) ended up with a BC-1T...833s and all.  The original transmitter was 1947 vintage Gates and yes it used 810s.  It was our standby after the new transmitter was put in service.  When we got the BC-1T it only ran 250 watts because the plate transformer (the one I have now) and filter cap were not made for 1KW.  It was in service for at least a year.  Then the station got a CP to run 1KW day and 250 night so a new plate xfmr and cap along with some other parts to convert it were added.  I think the owners knew we needed a new rig but didn't want to go with the KW/250 in case we didn't get the CP.  Oh well, their loss is my gain!  Mike - W9ZSL

[W9ZSL]

The Gates 250C looks a lot like the first xmtr at WOBT.  I know it wasn't a GY.