[Amps] Harbach SB-220 Soft Start Relay Part # or, replacement

[Adrian]

From: David Gow<6146guy at gmail.com>

Subject: Re: [Amps] Harbach SB-220 Soft Start Relay Part # or
	replacement
Message-ID:
	<CA+1A67SRN6bm2QFffKshYnsyyvcC1CQiQu4QCamCL+f94zb8KA at mail.gmail.com>
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Pull it all out, as has been well documented there is no need for a soft
start mod for th SB-220, it is built into the transformer. You are only
protecting the switch and an outlet strip will do that.



I thoroughly agree, I removed from mine soon after receiving. I also connected the
Filament transformer primaries directly together bypassing the shared HV primary ssb/cw switching to protect
against  switch fault or HV primary failure also taking out the filament transformer primary, by overloading
one side in such a fault.

It seems the soft start idea was more that most did not know the real reason for the 3-500z grid/filament shorts sometimes discovered,
and put it down to filament start current, which when tested is only 60% of Eimac max recommendation.

73

vk4tux