I couldn't help myself!...Does anybody have a manual for a Gates BC-1J?

[N0WEK]

The BC-610 may have to go on the back shelf since I couldn't pass up this transmitter...




Now all I have to do is go pick it up in Colorado.

Does anybody have a manual for this or any advice on conversion to 160 and 75?

It seems to be all there and unmolested but I can't find much info on this model on the web.

Lucky for me I have a tolerant wife!

Greg

[w3jn]

Congrats, Greg!  That's the one that was on eBay, correct?

[N0WEK]

Congrats, Greg!  That's the one that was on eBay, correct?

Yup, that's the one. I talked to the non-ham owner this morning and it seems to be all there and not obviously messed with. The only downside I can see at the moment is that it seems to have a weird audio driver circuit in that model but probably upgradable.

I haven't been able to find a schematic or manual so far but hopefully one will turn up.

I did see an expired Craig's List ad from earlier this year asking $1,500 for it, no surprise that it didn't sell for that. I figure I won't get hurt at $565; of course I still have to go retrieve it, but I'll be working in central Nebraska for a week in July and that's over half way there from Minneapolis and the company pays mileage.

Hopefully the iron and the 833As are OK.

Greg

[Opcom]

That's a real nice find there. Good luck on the book and please show us good pics of the insides when you get it home!

[N0WEK]

That's a real nice find there. Good luck on the book and please show us good pics of the insides when you get it home!

I'm going to shoot lots of pictures before I pull the iron and tubes before I transport it; at least then I'll have a prayer of getting it back together properly. I figure to get it up and running on the original frequency first before I attempt to convert it.

I was kind of amazed that there was only one bidder other than me, at the last minute.

The other one on Ebay at the moment is a Gates BC-1H that is missing some panels, all the tubes and has a bad plate transformer (the seller has a slightly smaller one included) and has a minimum bid of $650!

Mine is still a pig in a poke but looks good and seems to be all there.

Greg

[KA0HCP]

It's definitely a handsome unit.

[W7TFO]

I have the schematic in my stuff.  Somewhere....

I killed one of those years ago.  The driver is OK if you keep good 6L6's in it and keep it balanced out.

More to come when I get to that spot of 'storage', I'll pass it on to you.

73DG

[flintstone mop]

VERY nice TX. She's a beauty.
I looked at the BC-1H listing and that guy is out of his tree asking that much.
No tubes, Plate transformer shot, and the troublesome 807 audio driver.

Fred

[WA3VJB]

OH MAN.

Great-looking rig, especially those big Simpsons at the beltline and the observation window for the quad of 833A.

You also have the advantage of the old-style audio driver,  tube-type. Was it 6L6s ?  Later they had the 807s, which carried through the later "T" of the late 1950s, early 1960s, and the "G" model of the late 1960s, before being replaced by a HV solid state (and problematic) driver in the last of the line, the "H" series, production for which concluded by 1972 or 1973.

[flintstone mop]

OH MAN.

Great-looking rig, especially those big Simpsons at the beltline and the observation window for the quad of 833A.

You also have the advantage of the old-style audio driver,  tube-type. Was it 6L6s ?  Later they had the 807s, which carried through the later "T" of the late 1950s, early 1960s, and the "G" model of the late 1960s, before being replaced by a HV solid state (and problematic)    :odriver in the last of the line, the "H" series, production for which concluded by 1972 or 1973.

WHAT??? The Solid Hate driver was problems too?? Not enough ooomph from the 807's.
Fred

[N0WEK]

I have the schematic in my stuff.  Somewhere....

I killed one of those years ago.  The driver is OK if you keep good 6L6's in it and keep it balanced out.

More to come when I get to that spot of 'storage', I'll pass it on to you.

73DG

Thanks, that would really help!

There seem to be manuals around for most of the other versions of the BC-1, but not much on this one. IF I can't find a complete manual, it looks like much of it is the same as the other models, at least in the RF sections.

I love the window for the 833As!

[K5WLF]

Magnificent, Greg! 833As have great glowstuff. Hope it's all in good shape for you.

ldb
K5WLF

[KB5MD]

I had one of these but it was in such bad shape electrically that I ended up parting it out.  It had been haywired (Southern term) so many times with burned parts and all manor of other improvising. The poor thing had spent its entire lifetime at a small country station on a gravel road in north Louisiana.  There was so much red dust inside that the meter faces were actually a pale orange until cleaned back to white.  I cut the cabinet down and rewelded it to be 19" rack width.  There is a picture of the end product below.  
Send me your snail mail address and I can help you out with the manual.
 My only advice would be to put a 220v variac in the plate transformer primary because it will put out way too much power for the ham bands and will pop household circuit breakers quickly.  I had to replace the audio driver unit with a homebrew 6L6 p-p unit.  The original unit had the driver transformers toasted.

[N0WEK]

I had one of these but it was in such bad shape electrically that I ended up parting it out.  It had been haywired (Southern term) so many times with burned parts and all manor of other improvising. The poor thing had spent its entire lifetime at a small country station on a gravel road in north Louisiana.  There was so much red dust inside that the meter faces were actually a pale orange until cleaned back to white.  I cut the cabinet down and rewelded it to be 19" rack width.  There is a picture of the end product below.  
Send me your snail mail address and I can help you out with the manual.
 My only advice would be to put a 220v variac in the plate transformer primary because it will put out way too much power for the ham bands and will pop household circuit breakers quickly.  I had to replace the audio driver unit with a homebrew 6L6 p-p unit.  The original unit had the driver transformers toasted.

Thanks for the offer, Roy. That would really help getting it on the air. I sent you a PM with my address and details.

I saw that version of yours somewhere on the web when I was doing some research on the BC-1J, it looks pretty cool in the 19" rack version.

I'll have to keep an eye open for a big 240 volt variac.

Thanks again,

Greg

[N0WEK]

Well, I finally made it to Longmont, CO to pick up the Gates BC-1J.

I was thinking it was 36" wide but it's actually 42" wide. If it were an inch wider I couldn't fit it into the back of the truck. I've pulled the large iron and have about 2-300 lbs of it screwed to a plank on the right front floor, which will help with the weight distribution and space problems. I've got all the tubes well packed and padded.

I pulled the meter panel too; 4 small bolts and ten numbered spade lugs.

The whole thing is in fine shape and only needs a light dusting. I can see where one transformer on the Mod. deck cooked off, but it's got a nice factory replacement in place. No Hambone type kludge fixes and all the original transformers. Tubes look good, including the 833As. I do need to replace all the missing small bolts holding the 36" Mod. and RF decks into the cabinet since the past techs didn't replace them. It's not a problem standing in the station, but it'd be bad when I lay it on it's back and drive it 1,000 miles.











It turns out that one of the local stations had this and 2 or 3 other transmitters, a phasing unit and 10 kw dummy load in two storage units and let the go for back storage. The guy I'm buying it from got them real cheap at the auction, planning to just scrap them but did some research and decided to try to find them a home. All of them, including the 10 KW found homes but I think mine is the gem of the bunch.

I'm going to finish loading up in the morning and head back to Grand Island, NE for two more weeks of work and then back to Minneapolis, a total haul of about 1,000 mile with the transmitter in the back of a 1993 Mazda PU. I'm going to stand the transmitter up in the hanger while I'm in Grand Island.

[Mike/W8BAC]

Wow, that really is in nice shape Greg. I like the windows. One large window for the finals and two little peak-a-boo portholes for the modulators. Is that it for the iron in the bottom or do you have it pulled out and in the truck?

Mike

[N0WEK]

Yeah, that bottom compartment is just the relay board and the HV power supply. The coiled up wires are the 240 volt power feed and the two loose wires are HV wire leads for the Finals and Modulator. I got all the big iron out of it and screwed it down to a 2 x 12 on the front right floor of the truck...



Everything else, including the spare tire, meters, tubes, cloths and packing stuff went behind the seats...



You REALLY don't want to crash this truck!

The main unit went into the back with less than an inch to spare between the wheel wells and just fit between the gas cylinders for the topper window...





It didn't make the truck squat much and I got from Longmont, CO to Grand Island, NE in about 8 hours @ 65 mph. I'll put it in the hanger for the next two weeks that I'm working here and then reload it for the 540 mile trip back to Minneapolis.

I'm glad I didn't have to deal with these transformers for one of the 10 KW rigs...



There are three of them in there and they must weigh at least 600 lbs each!

[N0WEK]

The Gates really dominates the garage. I'll have to clear a space for it in the basement and install casters on the bottom of the cabinet. I'll have to pull both the mod and RF decks and strip it down to the cabinet to have any chance of getting it in the side door and down the stairs. I'll have about 3" clearance to the finished ceiling when the casters are recessed on the bottom plate of the cabinet.

I just pulled 265 lbs of transformer iron out of the front floor of the truck, cleaned it up and put it on the front porch...



Left to right...

Plate transformer......... 90 lbs
Plate swinging choke.... 70 lbs
Modulation reactor....... 56 lbs
Modulation transformer..37 lbs
Plate smoothing choke..12 lbs

All of them check out with an ohm meter.

The other transformers for the mod and RF decks are still in place on both decks along with the filter caps and survived the trip just fine.

[N0WEK]

A couple of questions if I might...

Does anyone have any info on the 8008AX rectifier tubes? One looks near new and the other looks like a well used MV rect. I can't find any real info on them. Does anybody have a couple they'd like to sell, or should I just solid state it?

What have other people done with the final tank circuits? I'm torn between preservation and operating convenience ; I could rebuild it into a conventional Pi output for 160 and 75 without changing the outward appearance by using the turn counters for bread slicer or vacuum caps and still use one of those nice variable. plate coils.

I figuring on using the parallel 6146 RF drivers by modifying the tuned circuits for 160 and 75 and feed it with a new chassis replacing the xtal oscillator and buffer with a buffer for an external VFO.

The only thing I plan to do to the mod deck is replace the several multi-section canned electrolytics since they look original. As far as I've seen so far those are the only ones in there, everything else is oil or mica caps.

Should I use a 240 volt variac on the plate transformer to turn down the wick or would feeding the 230 volt primary with 125 vac do the trick?

I'm planning to get it going on 1130 kc first, just to make sure it works fine in original form and then do the conversion.

I don't want to reinvent the wheel on this conversion and I figure there are quite a few guys here who've been down this road before.

[Bill, KD0HG]

A couple of questions if I might...

Does anyone have any info on the 8008AX rectifier tubes? One looks near new and the other looks like a well used MV rect. I can't find any real info on them. Does anybody have a couple they'd like to sell, or should I just solid state it

8008s are the same as 872s, but use a different socket. "Large metal shell super-jumbo 4-pin bayonet base". OTOH, 872s use a bayonet-base medium shell. I use a pair of 8008s in La Bamba, they'll last you a lifetime. Mine have lasted 20 years of service. Don't worry about them lasting, take your time and find a couple of spares. In a 1 KW rig, they last forever.

I get a nice winter sun tan from mine behind the glass windows of the power supply deck. Solid state rects don't have no soul.

Just remember, like any other merc vape rectifiers, if they've been tilted out of vertical, cook them without any plate voltage for a good half hour before firing them up for the first time or they might flash on you.

5 volt, 7.5 amp filament, 5,000 to 10,000 V. PIV depending on temperature, 1.25 amps average current per tube. A pair in full-wave will offer you 2.5 amps of DC to play with. My rig sucks about an amp of peak modulator current and another amp of final plate current, and the 8008s are loafing.

In the later BC-1s, Gates switched their transmitter plate tranny primaries between 120 and 240 DC for low and hi power operation. Very easy to do, just move one plate transformer primary lead from neutral to the other leg of your 240 volt supply. Takes a SPDT toggle switch or relay.

Muy Macho.

Rock on.

[WB3LEQ]

I'll have about 3" clearance to the finished ceiling when the casters are recessed on the bottom plate of the cabinet.

You may want to consider a rethink on this part.  When I added casters to the bottom of mine I made a "picture frame" out of 1/4' x 2 angle iron for the bottom of the cabinet to set into.  I then drilled and tapped the angle iron for the pattern of the casters mounting.  The casters were rated at 300 pounds and I used 4.  Even with 4 it has some overload rolling resistance so I bought 2 more casters to help redistribute the load. [They seem to over rate caster capacity these days...] I looked at mounting the casters directly to the bottom but the thin sheet metal of the cabinet had too much flexibility to suite my requirements.  The only other method would have been to plate the bottom of the cabinet with a piece of 1/4" or 3/8" steel plate cut to size.  This would have cost more than using the angle iron frame.  The transmitter is heavy enough to roll around on the floor without a huge possibility of falling out of the angle iron frame.  I still have the option of drilling through the bottom of the cabinet to attach the angle iron to the transmitter's cabinet base.

[WA3VJB]

Well, I finally made it to Longmont, CO to pick up the Gates BC-1J.

Tnx for the update.  Treat that poor Mazda to a premium oil change !!

I again said "COOL !" when this thread bumped back up.  That's a good-looking transmitter and I really look forward to hearing you on it.

Maybe shoot some video for a YouTube narrative ...

[N0WEK]

I'll have about 3" clearance to the finished ceiling when the casters are recessed on the bottom plate of the cabinet.

You may want to consider a rethink on this part.  When I added casters to the bottom of mine I made a "picture frame" out of 1/4' x 2 angle iron for the bottom of the cabinet to set into.  I then drilled and tapped the angle iron for the pattern of the casters mounting.  The casters were rated at 300 pounds and I used 4.  Even with 4 it has some overload rolling resistance so I bought 2 more casters to help redistribute the load. [They seem to over rate caster capacity these days...] I looked at mounting the casters directly to the bottom but the thin sheet metal of the cabinet had too much flexibility to suite my requirements.  The only other method would have been to plate the bottom of the cabinet with a piece of 1/4" or 3/8" steel plate cut to size.  This would have cost more than using the angle iron frame.  The transmitter is heavy enough to roll around on the floor without a huge possibility of falling out of the angle iron frame.  I still have the option of drilling through the bottom of the cabinet to attach the angle iron to the transmitter's cabinet base.

The reason I want to recess the casters is that I'm getting pretty close to the ceiling, even recessed. I thought of using a plate for the casters but all the transformers and such on the base are bolted directly to the 3/8" base, they just threaded the holes, and the bolts stick through the bottom.

I think I can get casters bolted to the base plate (6 is a good idea) using countersunk bolts to avoid getting in the way of the transformers on top. My only real concern is that everything above the baseplate is then hanging on the welds between the base plate and the cabinet sides; that cabinet is HEAVY!

I'll have to take a hard look at the whole thing. I wish I had the room to place it in the shack where I could get to both front and back and then it could just sit on the floor. If I could do that I'd make a clear back for it so the tubes would be visible, including those big 8008AXs.

[n2bc]

To get rid of the bolts poking thru the bottom, just thread a nut on the bolt first, screw the bolt in a few turns then jamb the nut to tighten the iron down.  It's not likely you'll be tipping the thing over once the iron is in place!

Something to be careful of....   I went overboard when I put casters on an RCA BTA-1 I had - 4" industrial monsters.  It rolled very easy - too easy.  I had it in my garage & the floor was gently sloped toward a center drain.  Not so much fun chasing 1100 pounds across the floor.

Last thing - I always worried about tripping and falling into the backside when I was 'playing' with the interlocks bypassed.  Keep the floor clear of wires, tools, meters, etc.  Mine invariably turned into a rats nest when I was working on the conversion.

Have fun!

73, Bill   N2BC

[k4kyv]

The audio driver is quite a JS setup.  A pair of off-the-shelf audio amplifiers each using a pair of 6L6s, and the 600Ω output of each amplifier driving one 833A. You have to be concerned that the 6L6s in each amplifier are balanced, and then that the two amplifiers are properly balanced with each other.

The earlier Gates model, the BC1-F, used a pair of 845's in pushpull to drive the 833A's. IMO, a much better way to go.  My BC1-T uses the direct-coupled 807 cathode follower circuit, which seems to work OK, but  I have a complete 845 driver stage that came from an RA-1000, including power supply and all transformers, that I am thinking of temporarily hooking up to drive the modulators in mine, and comparing performance.  If it works noticeably better, I might permanently install the Raytheon driver and pull out the 807 stage.

If those 1-J driver amp output transformers have 4-8-16Ω taps in addition  to the 500Ω ones, the driver amps would make a nice hollow-state stereo pair, if a real 845 driver stage could be found or built from scratch for the transmitter.