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THE AM BULLETIN BOARD => Technical Forum => Topic started by: KD1SH on September 24, 2022, 08:55:55 AM

Title: Greenstone Vacuum Relay
Post by: KD1SH on September 24, 2022, 08:55:55 AM
Ebay item 391918860078. Anyone have any experience with these? The description says "The relay will easily switch 5000 watts or more for an HF linear amplifier."

"Switch" 5000 watts or more - as in "hot" switching - seems doubtful, but with proper sequencing it sounds realistic. Decent price if it's really capable of that.

Title: Re: Greenstone Vacuum Relay
Post by: W3SLK on September 24, 2022, 11:44:05 AM
I remember reading sometime ago on one of the AMPS forums that Kilovac, who was the 'overseas alternative' to Gigavac went out of business. Maybe it has been resurrected as Greenstone. I think Greenstone makes tubes as well. Being that Henry Radio is selling them on eBay, I would expect them to be fairly reliable.

Title: Re: Greenstone Vacuum Relay
Post by: KD6VXI on September 25, 2022, 11:55:55 AM
Greenstone was one of the first Chinesium producers of vacuum stuff:  Relays, tubes, etc.

I was buying Greenstone direct back in the early 2000s and even a few things in the late 90s.

I have not purchased from them in a while because they don't sell direct anymore.  And when they started having the mark ups, weren't that much cheaper than Eimac....  I'm sure this might have changed with the prices Eimac are selling for now.

Kilovac was great.  So was Gigavac.  Gigavac you could tell them you where a ham and they had 'alternate' pricing.  Making them pretty cheap.

To me, from what I've heard from other builders lately, Greenstone might be a crapshoot.  I was switching YC156 based amplifiers with (a pair) of them in 2000.  Today, I'd find surplus.

Russian relays are also really good.  Way better than the spec's show.

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