Batboard

Hi All,

I recently purchased a VHF 2-channel Radius P50 HT from a Hamfest. I know it is not synthesized and is crystal-controlled only, does anyone know if it can be converted to 2M Amateur? Also, does the radio support duplex operation or just simplex?

Thanks!
David Craig N9VJF

David,

I have a bunch of these but I've never tried to put them on
2M. If by duplex you mean talk and listen at the same time
the answer is no; no HT does this. If by simplex you mean
PTT then listen the answer if of course yes. The P50 uses
separate receive and transmit crystals.

Personally I dislike working on the P50's board. It's very small
and reminds me a lot of the old HT-220 though the access to
the rocks is a lot easier.

Crystals from Bomar in NJ should run you about $15 each, if
you want to experiment with 2M capabilities. You will have
to do some retuning and the question is whether or not the
oscillator will "reach" down to 145/146/147 mHz.

Regards,

They will do half duplex for repeater operation.

dcraig5005 wrote:Hi All,

I recently purchased a VHF 2-channel Radius P50 HT from a Hamfest. I know it is not synthesized and is crystal-controlled only, does anyone know if it can be converted to 2M Amateur? Also, does the radio support duplex operation or just simplex?

Thanks!
David Craig N9VJF

Tom and Dave,

Thanks very much for the responses - yeah by duplex operation I mean being able to program a seperate TX and RX frequency (offset) for a repeater.

It is a two-channel unit, so basically I would have to program the repeater input on CH1 and the output on CH2?

Thanks again,
David Craig

No, each channel is controlled by two crystals, you'll need 4 in total for two channels.

Say your channel 1 is 460MHZ on a repeater, you'll need two crystals, 460.000MHZ and 465.000MHz in the first channel slot, and the same with channel two. You could make channel two the talk around, then needing two more crystals, 1 for TX and 1 for RX, on 460MHz

Simplest way I could think of to describe it.

I believe the P50's were capable of jumping crystals, so you'd only need 3. I'm not 100% sure of that, maybe someone else could answer?

601 wrote:I believe the P50's were capable of jumping crystals, so you'd only need 3. I'm not 100% sure of that, maybe someone else could answer?

Yes, the P50 has jumpers to allow reuse of the channel 1 RX and/or TX frequency in channel 2 so you only need 2 TX and 1 RX xtal for the usual repeater talk-around set up.