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 11 
 on: June 11, 2025, 09:03:58 AM 
Started by n5ama - Last post by n5ama
Good morning Chris,
I do not have the original choke and even if I did it looks typical of the nearly bullet proof construction that was common 20 years ago and probably filled with tar. The open frame chokes would be great and I have on rare occasion rewound smaller transformers that otherwise weren?t available, but in this case, I hope to find something that will fit and have close specs that I can use. I guess I could replace it with a larger choke and mount it external to the amp, but I plan to use the amp in its rack mount form and an external choke would be messy.

Thanks,
Tom

 12 
 on: June 10, 2025, 09:30:53 PM 
Started by n5ama - Last post by w7fox
Do you have the old choke?  It may be easier to rewind it.

 13 
 on: June 10, 2025, 11:37:43 AM 
Started by n5ama - Last post by n5ama
Thinning out the shack and up for sale is my RCA CR-88A diversity receivers along with a US Navy LS-139/G speaker unit and a Delta dual receiver pre-tuner. This is contained in a very nice FAA rack cabinet. All the equipment is in very clean condition. One of the two receivers isn't working, the other works very well. I'm not sure why one of the receivers isn't working but don't expect any major problem.

The receiver set is in the northwest Louisiana and for obvious reasons isn't shippable. The cabinet is equipped with rollers and is on the ground floor so loading shouldn't be a problem. I also have a hydraulic lift available. Additional pictures on request for individuals interested in buying this equipment. I'm asking $1000 for the set and there is very little wiggle room.
Thanks,
Tom N5AMA

 14 
 on: June 10, 2025, 08:31:25 AM 
Started by n5ama - Last post by n5ama
Hi Pete,
Thanks for the quick reply! I realize I need to put the dimensions with the request but won?t have access to the amp for another week. I?ll do that asap but in the meantime hope to find a parts unit, however unlikely.
Have a great week.
Tom

 15 
 on: June 10, 2025, 02:53:30 AM 
Started by n5ama - Last post by Pete, WA2CWA
You might want to provide the maximum physical dimensions in order for a replacement choke to fit.

The SDP amplifier is not a common amplifier that's found at many operating positions or familiar with amateurs.

 16 
 on: June 10, 2025, 12:20:05 AM 
Started by n5ama - Last post by n5ama
I?m looking for a choke that will fit in a SDP 1000L amplifier. The manual says its a 4-35hy swinging choke at 500ma and 2000 working volts. It?s a bit tight in the supply so not just any choke will fit. If you have a parts unit with a good choke or a choke that closely matches what might work, please contact me with what you have and what you want for it with shipping to 77429 (Houston, TX area).
Thanks,
Tom N5AMA

 17 
 on: June 09, 2025, 09:59:43 AM 
Started by KA3EKH - Last post by KA3EKH
Picked up a WS-19 at Hamvention, its a basket case so have no problems doing some modifications to it. Started by removing the VHF set and am now in the process of replacing tons of capacitors and lots of the old brittle wiring.
The goal is to end up with a another low power AM transceiver that I can run at events.
In addition to the VHF junk that's been removed they also had a intercom audio amplifier in the set and have been thinking of using that to drive a speaker or better yet as a modulator for the 807 in the PA. The existing circuit uses a grid modulation system but wondering if anyone ever used the 6V6 in the intercom amplifier to drive the 807 as a plate modulated transmitter? figure maybe I can find a old tube CB that I can take the modulation transformer out of.

 18 
 on: June 08, 2025, 04:11:37 PM 
Started by KE7NL - Jack - Last post by KE7NL - Jack
OK, sports fans!  Time to clean out the shack.  Here is a list of items looking for a good home.  I prefer pick up, or Hamfest, (Berryville, Nearfest -maybe) or meet you half way no more than 100 miles from DC.  I will consider any reasonable offer.
Kenwood Twins ? complete set.  R599A Rcvr, T599D TX (sounds great on AM), S599 Spkr, Connecting cable, Manual (to be sold as a complete set)
Heathkit DX 60 TX (un molested), HG 10B Vfo, Cable, Manual
Hallicrafter SX-140 Rcvr, Manual
Kenwood TS-520 Transceiver, Manual
Roberts Reel to Reel Tape Deck
Collins 51J-4 Rcvr (Howard Mills Restoration), Manual
TENMAX 72-300 (nice monitor scope)
Jack -  KE7NL@yahoo.com or 518 232 3102


 19 
 on: June 08, 2025, 10:48:27 AM 
Started by WZ5Q - Last post by WZ5Q
Howdy Y'all,

I recently got a hold of some disconcerting news which has forced me to re-evaluate my "Round-to-it" List. The Transmitters that were intended to get back on the air, as well as the ones I need to finish building, have been re-organized in priority. As much as it pains me to do it, I have decided to sell some of them. First on the chopping block is my RCA BTA-1M, 160m AM Broadcast Transmitter as I do not think I will ever get around to putting it back together. I have other KW Transmitters that will operate 160m, so it is really not needed.

The RCA BTA-1M, AM Broadcast Transmitter is the "Shutter Door" model with the roll top desk type of doors that open sideways in the front and rear of the transmitter. The cosmetics are fair with some scratches on the sides, and all the panels are there. This monster is on casters so it rolls around good. This model uses a pair of 833's for RF Finals modulated by a pair of 833's and uses 807's everywhere else except for the Rectifiers of course. I think I might have a few 833 spares and a set of "licorice sticks" for it. The transmitter was operating when it went dark at Mr. Steve's (K5LTK "Little Texas Kilowatt") QTH about 15 years ago. It has the original UTC Plate Iron, RCA 10H Filter Reactor, RCA Modulation Transformer, and the matching 50H RCA Mod Reactor. This transmitter has already been converted for 160m operation and was Mr. Steve's daily driver back in the day. Now I must say it has a liberal coat of preservative all over it as Mr. Steve was a chain smoker, so it needs a good hosing down. It no longer has a smell, but the nicotine coating is there for sure.

I also have the large factory blueprint schematic for it.

For your visual pleasure, you can see some Hi Rez pictures of it at my server link below.
Be warned these are Hi Rez and therefore are huge files.

https://www.wz5q.net/images/bta-1m/Trip%20home/

I am wanting $2700 OBO, to be picked up  here in Central Louisiana - 71341.
Shoot me an email if interested.
I'm good on QRZ.

73


 20 
 on: June 08, 2025, 09:37:23 AM 
Started by n5ama - Last post by n5ama
Found, thanks!
Tom N5AMA

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