National over Eimac or Econco

FM does it with frequency!
ChuckG
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Re: National over Eimac or Econco

Post by ChuckG » Thu Apr 05, 2018 10:30 pm

RGORJANCE wrote:
Thu Apr 05, 2018 8:49 am
Nearly as crazy as the old 5CX1500 war story.
If you are talking about the Salt Lake nickel plated tubes, I still have nightmares.
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Chuck Gennaro
Central Wisconsin

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RGORJANCE
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Re: National over Eimac or Econco

Post by RGORJANCE » Fri Apr 06, 2018 6:45 am

Yuppers, that's the one. They transferred the manufacturing process to another state, but somehow there was some slight of hand technique - unwritten - of course, that didn't get to the light of day and xmttrs were blowing up all over the country. Some lasted a whole 8-12 hours after tube change, some cratered with the application of HV DC! CLICK BAROOOOOOM!!! Smoke, fire, strange odors, etc. Fun!

How long did your's last???

Fossil

ChuckG
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Re: National over Eimac or Econco

Post by ChuckG » Fri Apr 06, 2018 7:49 pm

RGORJANCE wrote:
Fri Apr 06, 2018 6:45 am
How long did your's last???

Fossil
I put one in a Collins 2kW FM and hit the plates, lights went out, destroyed the socket.
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Chuck Gennaro
Central Wisconsin

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RGORJANCE
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Re: National over Eimac or Econco

Post by RGORJANCE » Sun Apr 08, 2018 8:18 am

Don't recall if I ever posted this before.....

Installed a Harris HT-5 waaay back in the early 90's. First factory new tube lasted well over 38,000 hours. Second tube - a rebuilt - lasted a year, third lasted back up in over 25,000 hours. Recent years, life has been pretty good with rebuilts.

Lately, our luck with ECONCO rebuilts has been relatively good, but did get two bad tubes for 10kw Harris and BE xmttrs. Warranty replacements seem to be holding up well. I think those were 4CX7500's.

We try to avoid the Chinese tubes as they have proved to be NG.

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ChuckG
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Re: National over Eimac or Econco

Post by ChuckG » Sun Apr 08, 2018 6:20 pm

RGORJANCE wrote:
Sun Apr 08, 2018 8:18 am
Installed a Harris HT-5 waaay back in the early 90's. First factory new tube lasted well over 38,000 hours. Second tube - a rebuilt - lasted a year, third lasted back up in over 25,000 hours. Recent years, life has been pretty good with rebuilts.
The rebuild in our HT-5 has chugged along for 39,420 hours and still has plenty of reserve. It''s still on reduced filament voltage.
The three previous rebuilds made it 12-18 months. There doesn't seem to be any rhyme or reason to it.
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Chuck Gennaro
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Joe Friday
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Re: National over Eimac or Econco

Post by Joe Friday » Thu Apr 12, 2018 4:18 pm

Just ordered a 4CX3500A rebuild today from Econco...apparently they had stock, as the tube shipped today.

Kevin

Kent T
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Re: National over Eimac or Econco

Post by Kent T » Tue May 01, 2018 9:10 am

RGORJANCE wrote:
Fri Apr 06, 2018 6:45 am
Yuppers, that's the one. They transferred the manufacturing process to another state, but somehow there was some slight of hand technique - unwritten - of course, that didn't get to the light of day and xmttrs were blowing up all over the country. Some lasted a whole 8-12 hours after tube change, some cratered with the application of HV DC! CLICK BAROOOOOOM!!! Smoke, fire, strange odors, etc. Fun!

How long did your's last???

Fossil
When that happened, and this is an old Gates FM1K, DC got applied, Click, BAROOOOOOM!!!, Smoke, Fire, strange smells, and the gnashing of teeth, and the liberal application of 4 letter words, none of them Love. And not so nice calls to Eimac.

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