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Tube Transmitters

Z

zachmorton

Maybe not the proper place to place this thread, but I am wondering. With Econco and Richardson (a division of Econco) basically being the only game in town for tubes, who is everyone using and what kind of results are you getting. Average of 1 in 3 rebuilds have come back bad and the cost for the rebuild has doubled since the takeover. They are attempting to push you to buy their brand new tubes (in my case $6500 for a 4cx20000d), and that's just not feasible in this economy. I have used Zonum in the past, but wonder about the quality of his rebuilds due to Econco's upping their prices. Any ideas? Thoughts?
 
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I've given up dealing with rebuilt tubes. Here's why: My Harris HT30CD, a brand new Eimac 4CX2000-C costs around $4,200.00. With proper filament burn-in and management, that tube has made 30kW for over five years and still counting. Had I used a rebuilt tube, I'd spend $2,600.00 and will be lucky to get 2 years of use. The upfront cost is higher for sure, but the payback is much better by going with new.
 
Do you think that would apply over other types, Kelly? I still have one Continental 316F (AM) in service. Also, everyone on one of the hills I work on is running Econco rebuilts (Continental & Armstrong 10 - 28kW). Can't remember that I ever heard someone suggest buying a new tube as a better alternative. Aren't the warranties comparable?

I had some run-ins with Zonum over dud returns. Other than that, I suppose his tubes worked as well as any. I'm getting 2 years on the AM Continental (Econco). I'm pretty sure the owners would choke over the price of a couple of new tubes. Haven't had the big FMs long enough to know about them yet.
 
Zonum, no thanks. Econco...high but they are easy to deal with if you have problems...I will stick with them until the rebuild price gets to about 75% of new...Thanks JBI
 
Grounded Grid said:
Do you think that would apply over other types, Kelly? I still have one Continental 316F (AM) in service. Also, everyone on one of the hills I work on is running Econco rebuilts (Continental & Armstrong 10 - 28kW). Can't remember that I ever heard someone suggest buying a new tube as a better alternative. Aren't the warranties comparable?

I had some run-ins with Zonum over dud returns. Other than that, I suppose his tubes worked as well as any. I'm getting 2 years on the AM Continental (Econco). I'm pretty sure the owners would choke over the price of a couple of new tubes. Haven't had the big FMs long enough to know about them yet.
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I haven't purchased any AM PA or modulator tubes in several years, so I can't comment on the difference between rebuilt and new for AM use recently. That being said, it seems to me that quality and stability of new with FM, should carry over to AM as well. I used to run rebuilt tubes in my 828E-1 'Power Rocks' at KJR with hit and miss reliability. As I remember, I'd be lucky to get about 9 months to a year from Econco rebuilt 15000A triodes. If the transmitter is strictly used in backup service then sure, rebuilt tubes make sense. I still maintain that the cost of running rebuilt tubes actually cost more in the long haul over new. Personally, I'd rather have less tube changes and three or more times the life for double the upfront cost. Try new sometime, you'll see what I mean.
 
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Large groups/markets will buy new tubes....small markets will buy rebuilts because of upfront $$ difference...though new tubes may costs lower when depreciated over the years it may last...last rebuilts I had were Econcos....and they started tripping off the air 6 hours after installation (and the site was 60 miles away)...but this was the wonderful YC130 (which even new was a PITA!! but then at 33kw, got about the same length of run time out of both new and rebuilt in that model (about 13-18 months)....if Eimac had developed the 4CX20000E earlier, I would have changed to that in a heart beat.......
 
Grounded Grid said:
Thanks for the perspective. I may give that a try. Speaking of KJR... I was told they once had one or two Ampliphase rigs. True? The station was really sweet sounding in its day.
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When I got there in 1988 KJR had the Collins 828E-1 Rock as the main and an RCA Ampliphase as a backup. The problem was, the previous engineer had taken the Ampliphase apart, probably because he didn't understand how it worked and wasn't able to keep it tuned up. I was nervous without not having an operational backup, so I put the Ampliphase back together with non-PCB caps and set it up via specific notes that Lee H (Ampliphase Master) had left behind. The Ampliphase worked well when needed, but really sucked AC out of the wall when used, plus wouldn't quite modulate like the Rock did.
I found a newer Continental version of the Power Rock with very low hours from a defunct "All Elvis station" (I'm not kidding) in Portland that had been seized for lack of transmitter site rent. I took the Ampliphase out of service, selling it to KKFX. The newer Continental 'Rock' went into main status and the Collins 828E-1 to backup. Ironically, the Ampliphase sat untouched at the KKDZ/KARR site in Kirkland for several years uninstalled, until being destroyed in a fire. In hindsight, I probably should have come up with a way to keep the Ampliphase there in West Seattle, but we were short on space and it would have been destroyed by the mud-flood after the Nisqually earthquake, as were both the Power Rocks anyway. Fortunately, the new 50kW site was completed and the proof completed, so we walked away from the West Seattle site.
 
Kelly A said:
When I got there in 1988 KJR had the Collins 828E-1 Rock as the main and an RCA Ampliphase as a backup. The problem was, the previous engineer had taken the Ampliphase apart, probably because he didn't understand how it worked and wasn't able to keep it tuned up.
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You just brought up a bittersweet memory.

In the late 60's, a station in Guayaquil, Ecuador installed a 10 kw Ampliphase on 560 AM. Their engineer was pretty much self taught, and did not know quite enough English to follow the RCA manuals and tech notes. So I got a call from them to look at the box, which had become the classic Amplifuzz and was annoying the local station on 540. I found that the site was not air conditioned... and was in a salt flat in the Guayas River tidal basin. This was just a couple of hour's drive south of the Equator, so it was hot and humid nearly all year long.

Guess what... they transmitter was not stable, and generally when they tuned it it became worse. I convinced the owner, a soap company, to put in an AC unit and better building ducts, and got it working right. But about every 3 or 4 months, generally when the seasons changed from the wet to the drier one, I'd be called to do the same thing again. It was fun and gave me a little pocket money. And made me very happy I built my own transmitters.
 
Ampliphase transmitters definitely weren't for stations without an engineer that could care and feed them on a regular basis in climate controlled conditions. And you're right David, the Ampliphase exciter used to do unpredictable things when kept too warm or too cold. Early solid state components (VCA's and transistors) used to drift, causing all sorts of strange behavior. I remember at KJR during the summer months, I'd avoid running the 'Funnyphase' because the site didn't have air conditioning, just positively pressurized room filtered outside air, and a large ductwork to carry the transmitter heat out. That being said, I'd still put the Ampliphase on the air at least once a month for several hours, just to make sure it was ready when needed.
 
I used both Econco and ITT (now Triton-if they're still in business) in the 90s in military 100kW transmitters. Econco's quality fell off the cliff in the mid-90s and I quit buying them. I have to agree that a proper bake in and transmitter balancing extend the life of a new tube and make them more cost effective over the life cycle.
 
Quick update: I spoke with a factory tech at Econco yesterday and they told me flat out that the particular tube that I use (4CX20000D) rebuilds will fail at the drop of a dime. No notice, no gradual drop, just die. She said that that particular design just does that, and you're lucky to get 1 year out of the tube on rebuilds. For new tubes, you get maybe 1 1/2 years or 2 years out of them, but that's about it. Are you serious! $6500 for a new tube and you only get maybe two years?? Sheesh.
 
The old EEV tubes, especially the 4CX15000A, would last forever.....That tube in a CEC 816R5B, like KEGL's, would give you YEARS of run time.....but when EEV discontinued the model, the rebuilds never came close....
 
zachmorton said:
Quick update: I spoke with a factory tech at Econco yesterday and they told me flat out that the particular tube that I use (4CX20000D) rebuilds will fail at the drop of a dime. No notice, no gradual drop, just die. She said that that particular design just does that, and you're lucky to get 1 year out of the tube on rebuilds. For new tubes, you get maybe 1 1/2 years or 2 years out of them, but that's about it. Are you serious! $6500 for a new tube and you only get maybe two years?? Sheesh.
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She's pulling your chain Zach. The main differences between a 4CX20000A through D is the fin size and heat dissipation. They are essentially the same tube. Now, does Econco struggle with rebuilding the D-series? Perhaps, that's true. As mentioned, I've gotten well over 6 years of continuous service out of new Eimac 4CX-20000C-series tubes. One of my former stations with a BE 35T, which I believe runs a 4CX-20000D, running at 38kW TPO. So far the original Eimac has lasted 10 years and counting.
 
The Ampliphase was on the air and running when I left KKDZ. Lee H came out to Kirkland to help get it on the air. That was fun.

Now I have a 317c-2 for a backup at one station and I'm just hopping they buy me an NX-50 when the tubes crap out. The main is an ND-50 and it's been running fine. As a matter of fact I think the ND-50 has been running even better now that I added some Sea Hawk decals to it, and the Sea Hawks have not lost since.

Go Hawk!
 
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