VK Logger Ham Radio Forum Archive

G'Day To All,

I have recently purchased an ACOM amp, which is the first amp I have ever operated.

The antenna in this case is a Dipole approx 100 feet in length.
One of the bands I mainly use this dipole on is both 80 & 40.
By default the Amp won't tune up on these two bands, so I need to switch in my MFJ-962D.

No, I am unsure what technique I should use to tune both the Tuner and Amp together.

How I am currently tuning is as follows:

Take the Amp out of circuit and tune the antenna with the tuner as normal. When I get that right, I switch the amp back into circuit. This typically gives me around 1.5:1 SWR on the readout of the Amp whilst the Tuner is pretty much indicating 1:1.

Once the LOAD & TUNE are set, I then turn back to the tuner to get the 1.5 closer to 1:1
I try and keep the TRANSMITTER knob where it is and tweak the ANTENNA/INDUCTANCE knobs to bring it down.

Which is does, but then pushes the SWR on the Tuner up around 1.5+

I now wonder if my technique is incorrect.

Any ideas?

Pete VK4CCV

Sounds OK to me, although I wouldn't bother adjusting the tuner a second time.
1.5:1 VSWR is only a 4% power loss (<0.2dB); just accept it.

Hey Ian,

Thanks mate, sounds like a plan.
I am one of those people who like to have everything perfect .

Thanks again Ian.

Pete