Mike,
If it were my amp, I would be very happy and just get on the air and make
some noise. I wouldn't get too bent out of shape over other guy's claims.
I'm sure the guy who gets 2 kw out on ssb also has a car that goes 300 mph
and a kid who has an IQ of 187.
If you are concerned, get some sighted help to check the HV meter on both tx
and standby and see how it compares with specs. Maybe let him watch the
meters as you tune up so you can be sure you are getting the most out of it
without going beyond tube ratings.
One thing I noticed in your tuning process: You seem to go plate, load at
low drive, then just load at full drive. Everything I've ever seen or
heard on the subject seems to suggest that you adjust plate, load, then
back to plate and then load again at low drive, then the same thing at full
drive. There is some interaction between the 2 controls, so you need to go
back and forth between the 2, always ending with the load. It's how I tune
my AL-80B and it seems to do fine.
73, Steve KW3A
----- Original Message -----
From: "Michael Ryan" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, November 10, 2009 2:36 PM
Subject: Heathkit SB-220 pwr out questions.
> =20
>
> =20
>
> Hi all:=20
>
> =20
>
> I've been running a Heathkit SB-220 HF amplifier for the past 5 months =
> and the overall output #s, aren't on par with a couple of other 220s =
> that are in operation in my area.=20
>
> My Amp is bone stock and original tubes. I don't know if the other amps =
> are because I don't know the operators personally., only one.=20
>
> The #s they claim are 100W in =3D 1KW CW, 100 in =3D 1800/2KW SSB.
>
> I use an LDG Electronics TW-1 meter.=20
>
>
>
> Here's my amplifier tune up procedure with my antenna tuned to a 1 to 1 =
> SWR.=20
>
> =20
>
> 1. Set the Exciter drive at 10W, CW, on desired band.=20
>
> 2. Place the Amplifier in the CW/Tune position on same band.=20
>
> 3. Key the exciter and amplifier, adjust the tune control to increase =
> the pitch of my meter, about 10 seconds of key down, return to receive.=20
>
> 4. Key the exciter and amplifier, adjust the load control to increase =
> the pitch of my meter further, about 10 seconds of key down, return to =
> receive.=20
>
> Key the exciter and amplifier to get a reading: 10W in =3D 170 out.=20
>
> 5. Place the amp in stand by and increase the exciter's drive to 100W.=20
>
> 6. Key the exciter and amplifier, adjust the load control, increasing =
> the pitch of my meter to its maximum, about 10 seconds of key down, =
> return to receive. =20
>
> Key the exciter and amplifier to get a reading: 100W in =3D 1030 out.=20
>
> 7. I switch the amp to SSB, leaving the exciter in CW, key the exciter =
> and amp to take a reading,=20
>
> 100W =3D 1237 out.=20
>
> As my meter requires a continuous carrier to function, this is why I =
> leave my exciter in CW and switch the amp to SSB for the final reading.=20
>
> I reduce the drive to 75W, with the exciter in CW and amp in SSB, I see =
> about 1KW out.=20
>
> LDG Electronics claim that there is about a 5 to 10 percent inaccuracy =
> on the measurements.=20
>
> Should I be concerned about these figures, are they normal, should I =
> consider replacing my power supply components and or tubes?=20
>
> =20
>
> Thanks & 73:=20
>
> =20
>
> Michael De VO1RYN=20
>
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