Thursday, March 28, 2019

ZETAGI power amps for 43 MHz

ZETAGI is a brand usually associated with CB radio products for 27 MHz although it seems that they also make RF power amplifiers for Italian CB band at 43 MHz.

The B149 and B129 models are shown below. Note that the Irish regulations for 30 to 49 MHz stipulate a maximum power output of 50 watts PEP.


This is designed for 42-44 MHz and runs off 12v DC. It's likely that it will work down to 40 MHz as well although the power may be slightly reduced.

Note the AM / SSB switch on the right is missing and is just a blank plate. It would seem as if this unit is very similar to the B150 27 MHz model and uses pretty much the same hardware for the B149 43 MHz model.

The B149 amplifier is intended for increasing the output power of 43 MHz FM transceivers so there is no need for a TX/RX delay to stop the relay clattering on SSB. As such, it is not suitable for SSB and is more suited for just FM and CW.


This model runs off the mains (230v AC) and has a higher output of 100 watts.

There doesn't seem to be any AM / SSB switch and is probably just designed for FM.

It's not obvious if this amp is linear or just running in Class C i.e. suitable for FM only.

As of March 2019, this amp is for sale for €225 in Italy. Note that this amp is not listed in the Zetagi website so it may be a discontinued model.

1) Zetagi website
2) B129 amplifier for sale


PE4BAS, Bas said...

John, I think the B149 is in the same enclosure as the 27MHz B150. You can see that they use the same front but the switch has blanke plate in it (hope that is the right word for it). 73, Bas

John, EI7GL said...

Now that I look at it Bas, I think you're right. They probably just use a modified version of the B150 to work on 43 MHz.

When I saw SSB on it, I thought it was just a Black switch but when I compare it to the B150, it's probably just a blank plate and the 'SSB' on the front panel actually means nothing.

I've updated the text in the post to make this clearer.