Boomer 400 DK input too low?

I have the following:
Stryker SR-655HP turned down to 1 watt DK by Clay's.
Boomer 400 linear
TX Star DX 250 linear (no knob)
LMR4-400 rg8-u coax & 6 foot jumpers
Dosy 4000 meter (after radio & a mp)

When I key up the Boomer @ 1watt dk with the "pre amp" selector switch on, my radio's swr alarm goes off.
With the pre amp switch turned off, it's fine. No swr warning.
If I turn the radio dk up to 2 watts and key up ( pre amp switch on), it works fine...no swr warning.
The Texas Star does fine either way and is fine. The Boomer is the finicky one.

So bottom line is... low 1 watt dk and pre amp ON, get swr warning on radio.
2 watt dk on radio, pre amp OFF radio swr warning does NOT go off.

SWR is below 1.3 on meter with or without amp on.
Weird! Too low of a dead key maybe?

Thanks

Swapped 6 foot coax from radio with a 3 foot and problem gone. Errr, rather covered up. Cheatin' the meter. Must be some sort of an amp mismatch. Any idears are welcome.

9C1Driver said:

I would not run either of those amplifiers with that radio, it's way too hot. Even at a 1-2 watt dead key the radio will still swing to the point it will overdrive them. An amplifier with four 2879 finals would be the smallest I would run.

The only way that radio will work is if you have it "de-tuned" so that from a 2 watt dead key it swings say 12-20 watts. That kinda defeats the whole purpose of buying an HP radio in the first place.

Those Boomer-Gray-Palomar 400 amplifiers were known to have impedance mismatches. Owners are always messing around with jumper lengths to make them work. You don't want to blow any of the discontinued finals in either of those amplifiers, replacements will be very expensive.

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Agreed. I went ahead and hooked up my ol' Galaxy dx73v (.5 watt dk) in the place of the Stryker.
I'll run the 655 barefoot until I can find a different heater. Thanks for the advice.

NZ8N said:

Boomer/Palomar and similar use 2 relays, one for main (TX/RX) and one for Preamp. When the Preamp is on, it adds extra length to the input path from radio to the amp stage, this extra on board length can cause your SWR indicator to false.
The Texas Star only uses 1 relay, the Preamp is passed through the Preamp switch, and bypassed in TX mode.

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Thank you.

I go out and get a FatBoy 4 pill 2879 w/variable (as suggested) and come to find that my radio isn't cutting the mustard on driving this thing. 2 watt dk, 32 watt swing doesn't appear to be enough. It appears that my radio wasn't tuned at Clay's....it had the modulation turned up a little and was converted.
Radio is running at 13.8v and amp at 14.3v