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Just of curiosity...

Outside of kits/ham produced prototypes, Do you know about any commercially produced 6m handhelds?

Should be technically feasible despite the fact that it would be more cumbersome than VHF / UHF radios, But I recall that CB operators have 27 Mhz handhelds.

Do you know the historical/technical/marketing other reason for them not to exist?

Or maybe they do exist and I cannot find any positive info about them...

rodv92
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4 Answers4

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The Yaesu VX-5R had/has 50-54 MHz FM, 5 watts. Nice compact little radio!
The VX-7 and VX-8 can also transmit 5 watts FM on 6 m, and 1 watt AM. None of the 3 will transmit SSB.

It had a little extension of the rubber duck to make it work at 50 MHz, though I doubt it was very efficient.

Antenna calculation:
The whip is about 25 cm long, so I'll consider a 0.5 m dipole. Radiation resistance the dipole is 1.4 $\Omega$. Reactance is about -1500 ohms, resonating this with a coil will introduce the rest of the 50 $\Omega$ resistance, probably giving a reasonable match. Efficiency is thus about -15 dB.

Further thoughts:
When talking to someone with a full-size dipole, like a repeater, the gain of the 6 m antenna will be partially compensated for by the reduced path loss. The path loss is 6 dB smaller at 6 m, compared to 2 m. Assuming the gain at 2 m is -3 dBi, and the gain at 6 m is -15 dBi, at 6 m the handheld will deliver only 6 dB less signal to the repeater.

webmarc
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tomnexus
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  • +1 but the term "resonate" is perhaps misplaced since I doubt the antenna system is anywhere near fully resistive (i.e. +j0). – Glenn W9IQ Aug 22 '18 at 22:34
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    You never know! There might be a resistor in there ... remember, a dummy load has a fully resistive impedance ;) – Scott Earle Aug 23 '18 at 01:01
  • I meant the sharp dip in VSWR that indicates the power is being absorbed by the coil's self resonance, instead of reflected back to the transmitter, i.e.something went XL=XC. The whole antenna might have gone through zero - I think I measured it once on a VNA, will post a graph if I can find it. – tomnexus Aug 23 '18 at 05:57
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    Same with the VX-8DR - advertised as 4 bands in the US with 6m, 2m, 1.25m and 70cm. It's utterly useless without a real 6m antenna, which means it is no longer a handheld. – user3486184 Aug 23 '18 at 07:37
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    I've used the vx-8 once on 6m at a hamfest, because all the other bands were full. It was effective with the stock antenna at least short range. Don't forget that they make CB handhelds too, so if 11m can work, 6m can work. – user10489 Aug 24 '18 at 11:26
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    To say that the VX5R is useless without a longer antenna is not based on first hand knowledge. Indeed the factory provided antenna is less than optimal; however, a range of communication between two points, exceeding 20 km or more is not unusual. In addition, there are 6M repeaters all over the country that extend the communication range to over the horizon distances, sometimes better than 200 km, depending on location. Bear in mind that 50-54 MHz falls in the middle of the Military band (30-75 MHz). Military radios are not any better than our ham equipment and the HT military radios use short – Dr. Flywheel Aug 26 '18 at 05:44
  • @tomnexus I added a little more detail on the vx7 & 8 based on personal experience, hope you don't mind! Seemed more appropriate than adding another answer. – webmarc Jul 14 '21 at 14:15
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    I have a VX-7R and I can certainly pick up the local 50Mhz repeater traffic quite well from inside my house. Traffic is much more readable using the little extender on the antenna. There are lots and lots of aftermarket antennas, including some more appropriate for serious 6m work. As an aside Yaesu ships (AFAIK) identical hardware around the world, so you can easily tweak the firmware to get xmit on the bands legal in your region. –  Jan 10 '22 at 16:39
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Wouxun KG-UV7 is available in

  • 2M/70cm (UHF 420-450 MHz)
  • 2M/1.25M (220 MHz) and
  • 2M/6M (50-54 MHz) frequency ranges.
tomnexus
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Mark Shreves
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Also the Cherokee AH-50, which is the 6m big brother to the AH-27 (CB variant). They were produced from about 1995 to the early/mid 2000s. FM-only and able to use with repeaters. Very basic radio but back then, choices were limited to this radio for a 6m ht/handheld.

Phil
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I have an Icom IC-T81A that will transmit and receive on 6 meters.

https://www.universal-radio.com/catalog/ht/3795.html

Or at least it did at one time. I haven't used that feature in a long time and my IC-T81A has seen better days. I haven't even powered it up in quite some time.

MacGuffin
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