Batboard

Hello,

I'd like to test the performance of a Harris antenna (RF-3150-AT152), which is a foldable 48.5" design, with some GP380 (HT1250) handheld radios. The radios are low band (29.7–42MHz).

Is anyone aware of any adapter allowing a TNC antenna on the Waris series radios?

The GP380/HT1250 use MX type connector or SMA? I've read posts mentioning one or the other... By looking at the Motorola BNC adapter #HLN9756, it seems to be a male SMA?




Thanks!

Mike

They have an MX Connector. If you find an adapter let me know i’ve been looking. Best option may be an antenna separation kit.

Another less desirable alternative would be using the Motorola adapter above followed by a BNC to TNC adapter...

I think attaching one of those giant whip antennas to an HT1250 in itself (assuming you had an antenna with a native MX connector) would put an excessive amount of stress on the antenna jack. Even more so with two adapters.

I’m assuming this isn’t an application where the radio could be separated from the antenna with a cable, I.e. body armor.

No, I wasn't thinking of separating the antenna from the radio.

I'll buy two adapters while I'm searching for a single adapter and see how well it works. I'll post a pic of the setup.

It's an MX threaded adapter but not an MX flat base. OP's pic looks a lot like the OEM RF adapter for the Waris radios

It won't work well and depending on how it's adapted might now work at all. The base of the Harris antenna has a series of matching components to try to keep it relatively low (well usable) SWR in the Vhf low areas. They need a ground reference. That adapter posted is for a GP type of radio with the headphone type jack used for RF.

The closest would be this but you still need to find a ground since the ground is isolated due to the plastic housing. You would have to fabricate something.

Hi,

Just tested the Harris antennas with the GP380s but the results were disappointing...

I used 2 adapters together, from GP380 to BNC and from BNC to Harris.

I placed one radio in the hands of my assistant, who was on the ground floor of a 2 storey house, and walked away with another radio. I maintained comms with either antenna up to 500m (straight line measured with Google Earth). This was in a densely populated area of 2 storey houses in a relatively flat terrain. Frequency was 29.70MHz, power setting was high.

There was no advantage in using the Harris antennas... Photos below.

Can anyone recommend a better antenna for lowband than the stock Motorola?

Mike

Just tested 2 WIMO (Germany) 10meter telescopic antennas using the BNC adapter, under the same conditions as above. Result was also the same... lost comms at the same spot. Extended length is 140cm.

Photos of the setup below.

Could be a ground plane issue with the Waris and those antennas. A field strength meter would be helpful. You could use a VOM with a diode between the leads for a crude measurement device

I can repeat the tests with a cointerpoise. What length would you recommend?

I would put a wire counterpoise off of the ground side of the antenna trailing along the ground and see what you get.