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Author Topic: Comparison of new 3-500Z triodes  (Read 25688 times)
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John K5PRO
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« on: January 25, 2006, 06:27:46 PM »

Attached is a short summary of my recent experience buying two 3-500Z triodes and their chimneys. "Caveat Emptor".
I hope the PDF format comes out.
73
John

* 3-500 comparisona.pdf (482.69 KB - downloaded 8563 times.)
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K6IC
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« Reply #1 on: January 25, 2006, 10:27:32 PM »

Very Interesting, John.   Thanks for the post.  Will be looking for the post mortum on your tests.

73  Vic  KF6RIP
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Vortex Joe - N3IBX
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« Reply #2 on: March 29, 2006, 11:58:29 AM »

John,
       I too, found it very interesting. Considering their warranty, I always though the "RF Parts" branded 3-500ZG to be a good tube.
Regards,
           Joe Cro N3IBX
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Joe Cro N3IBX

Anything that is Breadboarded,Black Crackle, or that squeals when you tune it gives me MAJOR WOOD!
stansub
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« Reply #3 on: December 09, 2007, 06:37:50 PM »

When I purchase 3-500Z's, I buy Amprex, ONLY!!!! Never a problem.  I have two amps using them, AL-82 and SB 221.
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Steve - WB3HUZ
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« Reply #4 on: December 18, 2007, 01:05:31 PM »

Been using the RF Parts ZG's for over five years in two different amp with no problems.
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Patrick J. / KD5OEI
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« Reply #5 on: January 11, 2008, 11:06:08 PM »

I bought these Chinese 3-500ZG tubes from ESRC. The warranty begins when they are first put in service and is for a year. quite friendly. I tested them initially by dissipating 1KW DC in a pair with zero bias for 30 minutes. I found no hot spots and the currents were reasonably equal. The attachment shows the Chinese tubes in the modulator. There have been no problems. Image attached. Looks like the same tube sans the rectangular logo?

Had I received such an obviously defective tube as the one in the PDF, I would have returned it for a replacement. I do not like the vendor of the Chinese tube shown in the PDF because they are unfriendly. I bought some RF power transistors from them and discovered that they in effect have no warranty. I was told by that vendor that they test them beforehand and then it's on the buyer, because "people blow them up and return them".


* 3500zchas6.jpg (242.45 KB, 1024x768 - viewed 3633 times.)
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