New Transmitter

[ka4koe]

Made a deal on a BC1T. I will be setting forth on the sojourn in a couple of weeks, pulling a U Haul trailer. If I'm lucky, I'll have it back up and running by the fall. It was retired from 1490 WWNB New Bern, NC, a year so ago as a working backup. The TX originally operated from 1590 WAWA Milwaukee, Wisconsin.

It was a tough decision. Another TX was available but the weight factor ended up being the deciding one. The TX is uncoverted.

Philip

[Opcom]

Be sure to take pics when you arrive and load it! travel pics are always fun!

[ka4koe]

Photos sent by the seller...

[ka4koe]

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[ka4koe]

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[ka4koe]

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[ka4koe]

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[ka4koe]

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[steve_qix]

Wow, that's nice and it's going to be QUITE a project !!  We'll be watching your progress.

[ka4koe]

Was looking at replacement rectifiers. Of course, no way am I going to go with Mercury Vapor. See this link:

Pair of 833s modulated by a pair, 4000 watts peak @ 2500V B+ equates to 1.6A peak current.

Rule of 4x your working voltage for PIV = 10 KV. Get conservative and run with the 20 KV rated unit at 1A...

Since 1A is below the constant current rating of 1.6A, parallel two for each leg of the HV.

Am I on the right track here? The rectumfryers go for about 5-7 bux each. Need 4, so perhaps 30 dollars spent to replace the 8008s.

Philip

[W7TFO]

Why the MV prejudice? Internet myth?  Too lazy to preheat?

I offered you good ones for free...

That TX has personality one, silicon has none.

The Xenon tube is a 4B32, not a lot of good glow, true.

Of those I have not one.

73DG

[ka4koe]

Simply slipped my mind.

[Opcom]

Thanks for the pron and the great nameplates! Mercury gives a homely warmth and glow, cozy like.

[KC4VWU]

HV rectifier stacks are cheaper than a replacement fil.transformer for the MV toobs... easier to find also. With the tx. in another room with the front door closed, you'll never see 'em anyhow. On the other hand, MV rectifiers in an old buzzard HB rack setup; mighty FB OM! HI HI!! 

[W9ZSL]

When I got started in broadcasting the transmitter was a BC-1T which wan't more than a few months old.  In fact, I was a janitor at the station and helped with re-wiring and remodeling the studio.  Went on the air for the first time on my 16 th. Birthday.  I worked for the station a couple of times over the years and was on the air in the mid-90's when the HV transformer shorted out and the Gates died.  I was there when it went on the air for the first time and was there when it died.  The rectumfryers had been replaced with with all solid-state National direct replacements.  A few years later, the transmitter was hauled out by the tower and covered with a tarp where it sat for a few years of Wisconsin winters.  I got permission to salvage it about 15 years ago which I did.

If you can score some of those solid-state jobs, I'd go with them rather than kludge together something equal.  They work great, no modifications are needed, and are direct replacements.  The driver boards look like they will need work.  That was a big problem with our's as well.  Components kept frying and unfortunately the engineer was a total lid who wasn't particular with replacement parts.

I still have some parts from the beast along with a manual.

Mike
W9ZSL

[Opcom]

One thing I do not like about that transmitter and others is using circuit boards for power tubes. They are always black in the end.

[WBear2GCR]

The rectifier tubes provide some time delay on dumping the HV B+ to the plates - unless there is a contactor in the circuit (?), so watch out for that issue when going to solid state rectifier - that and inrush current when turning on the AC mains.

Looks sweet!

Where is it going to sit, in the living room?

                          _-_-

[ka4koe]

Bear

It's going to sit in the garage directly, and I mean DIRECTLY, below my shack. Cable runs will be less than 15'.

Road trip is this Friday to hook up with K2DX Fred.

PAN

[WBear2GCR]

So, then you will be installing a "chair lift" in the floor so you can push a button, and descend directly below into the netherlands in order to quickly tweak the tuning and return to the operating position??

                            _-_-bear

[ka4koe]

No, simpler than that.....

1. Pair of FRS Walkie talkies.
2. Video camera aimed at TX meters.
3. Adolescent minor.

Procedure:

1. Send whining adolescent to garage below.
2. Issue destructions via FRS radio.
3. Watch metering on CCTV display during implementation of destructions.

[Opcom]

Perfect!

[W9ZSL]

BC-1Ts have contactors in the HV.

[ka4koe]

Now K4SMN sez....."Why don't we build a little shed out back to locate the transmitter?"

Good news: Sheri has accepted the fact that this is the new home of WAWA 1590, Soul, RB, and Jazz.
Bad news (maybe): I have to formulate an engineering / economic analysis to say why we're better off with the TX in the garage directly below my feet in the shack.

[w4bfs]

just quote a lot of statistics .... you might even believe them urself after a while

[K9DXL]

Just suggest that the combination of concentrated RF power and high voltage components will take care of any rodent problem you may have in the garage.