Hr2510 W/texas Star Dx350 SWR decreases during modulation

[Quiksilver]

Situation:
HR2510 (DK 1.25w) - Texas Star DX350 (non-var) - Turner +3 at 9-o'clock - I-10K antenna. SWR is virtually flat with no amp. With amp on and "dial-a-watt" (green button)depressed, my SWR at DK is at 1.5:1, and during modulation, SWR drops to 1.1:1. I'm seeing 75w DK swinging to 275w and an amp draw of 18 at DK down to 15-16 at modulation on the Astron 35M. SWR meter is the PalStar PM2000.
Is this normal?

 

[paws264]

Situation:
HR2510 (DK 1.25w) - Texas Star DX350 (non-var) - Turner +3 at 9-o'clock - I-10K antenna. SWR is virtually flat with no amp. With amp on and "dial-a-watt" (green button)depressed, my SWR at DK is at 1.5:1, and during modulation, SWR drops to 1.1:1. I'm seeing 75w DK swinging to 275w and an amp draw of 18 at DK down to 15-16 at modulation on the Astron 35M. SWR meter is the PalStar PM2000.
Is this normal?

Where is your SWR meter installed, between the Radio and the amp or, between the amp and the antenna?

.

 

[Quiksilver]

Radio - jumper - amp - jumper - meter - jumper - filter - antenna

 

[gamegetter]

it ok

1. do not check swr with modulation.
2.Voltage/current=resistance.

 

[9C1Driver]

Yup, thats normal. Only check the SWR on AM with a dead key and the mic gain backed way down.

 

[Toll_Free]

That's typical.

Since the amplifier is designed for 350 or so watts output, the transistors are at their 'designed for' impedance only during peaks. If you where to run the carrier up to max, the swr would be the same as it's showing with the voice peaks (within reason. AM by definition generates some distortion, and it's HARD to read it correctly with a standard meter).

You can use a single tone on AM, max the carrier out, or a single tone on SSB to read SWR.

You're amplifier doesn't reflect 50 ohms at the antenna port when it's doing 75 watts. What you're seeing is normal.

--Toll_Free

 

[Beetle]

The pointers on that Palstar might be moving around while you talk, but the point at which they cross should not be that much different from one instant to the next. That's the point you have to watch, not the individual pointers themselves.