220 Making a Comeback?

[902]

Can you put a VHF Spectra on 220?

 

[CommJunkie]

There are two 220 repeaters in my area that I can think of, and they are both linked to 440 repeaters. So, it doesn't make sense for me to spend the money on a 220 rig when I can talk to the same people from my 2/70 rig.

 

[902]

There are two 220 repeaters in my area that I can think of, and they are both linked to 440 repeaters. So, it doesn't make sense for me to spend the money on a 220 rig when I can talk to the same people from my 2/70 rig.

I started to respond earlier, but I ran into this off-topic raga. Very long story short - Linked repeaters have been supplanted by multiband radios. It's just easier to be on band, and it's impossible to buy a stand-alone amateur 440 radio anymore (I would love to have like an IC-47H again). But if a 220 radio falls in the woods and there's nobody around, does it make a sound? What I mean is that if everyone is talking on 440, and nobody's on 220, what have we achieved (except for making the electric meter spin faster)?

220 stands alone. It's got the best of both worlds in VHF and UHF. Propagation characteristics very close to 2 meters, antenna length and convenience of 440. Thing is that only repeater builders really see that. A 220 radio looks like a 2 meter radio, or even a 440 radio with the only difference to the end-user being the antenna on the car or HT. For people who've never used it, it's a lot like 6 meters, which is a little like HF and a little like VHF. If you've always worked one or the other, and you don't know what's in between, the experience can be thrilling.

 

[msa]

Can you put a VHF Spectra on 220?

I'd say no, or at least not practically, given the receive filters and synthesizer in the Spectras.

First, you'd have to be able to get it programmed up for 220, and get the radio to accept that codeplug.

Then, you'd have to get the VCO to lock on every frequency you intended to use. The VCOs in the Spectras involve laser trimmed capacitors, so you're going to have to de-solder the shield, and re-trim those by hand for the target frequency, as well as replace quite a few components to get it to go up that far.

Finally, there's the receive filtering.

They were top-tier public safety radios, very solid, great filtering...unfortunately that filtering makes taking them out of band (or even slightly rebanding one of the ranges) a chore.

Many of the VHF Spectras floating around out there are the later models made overseas...most of them will need capacitor replacement as well. Not too much of a chore once you've done a few (I certainly have, I use them on 2m, 440 & 900), but still, some effort required.

I think getting it to 220 would be impractical. Someone with a service monitor, the Spectra RSS, a lot of skill and time on their hands could /theoretically/ do it, but I suspect the end product would not be worth the time and money invested.

I think it'd be down a bit on transmit power as well, from memory the equivalents at least for the internal part number for the VHF High PAs were only rated to 180-200 MHz. They should work on 220, provided you changed the filter SMT capacitors across their leads (well, flats, anyway), but I bet you'd sacrifice some power in the process.

I'd say start with a Wouxon and make sure there's enough 220 activity in your area, first.

 

[fineshot1]

Maxtrac on 220

Well it does work for the Maxtrac, the tough part is the amplifier without
butchering the amplifier pc board but since they are plentiful it seems
interesting.

A step-by-step conversion of a VHF Maxtrac to the 220 MHz

 

[msa]

Well it does work for the Maxtrac, the tough part is the amplifier without
butchering the amplifier pc board but since they are plentiful it seems
interesting.

A step-by-step conversion of a VHF Maxtrac to the 220 MHz

Right, the MaxTrac was a lower tier commercial grade radio, much less filtering in your way... really just component changes. The Spectra is a whole other animal, though.

Intersting link, and thanks for it -- but man, by the time you have a shop mill out the PA deck area, and replace the PA, just to get a > 2W 220 mobile, you might still look for an older 220 mobile. Conversion looks fun to do but it's borderline on my personal hassle/reward scale. It was easy right up until you have to butcher and replace the PA. Then it starts looking like you'll have a commercial radio with slightly better receive sensitivity than an older 220 ham ring, but no more filtering, and programming required.

(Still, at least it's borderline, and not way, way over the border, like I envision the Spectra work being. Of course, every ham has to make that decision for themselves. Thanks again.

 

[902]

I used to work on both Maxtracs and Spectras when they were in current production and I worked in land mobile repair. I would say everything east of Micors and Mitreks were difficult to get out of band. I had a Syntor-X9000 on 440 which required some mods on the preselector. I ended up taking it out and subbing the stock preamp board for it which compensated for the cut-off. I knew about using the Murata filters for 900, but never saw anything like that for 220. It would be an interesting proof of concept. I've got a service monitor, an IR bonder, and a bunch of other testing and building stuff, but the things I don't have are time and ambition.

I have quite a few Maxtracs, M100s and GM300s I've accumulated since the 90s. They're all getting flaky now. I'm guessing the tantalum and electrolytic caps are devaluing. I saw an article on Spectra refurbs where the caps leaked and the electrolyte corroded the circuit board. If I'm going to keep these things going, I'm going to have to find the time to tear into them. Thanks for posting the link! I'm going to go look at it. I really like the Repeater-Builder website; it would have been so handy back in the day.

 

[zz0468]

I'd say no, or at least not practically, given the receive filters and synthesizer in the Spectras.

First, you'd have to be able to get it programmed up for 220, and get the radio to accept that codeplug.

The filters and VCO are quite tunable, and getting the software to accept the frequencies is trivial, but I don't know if they could be moved quite that far. The UHF, 800, and 900 Spectras can be moved about 50 MHz out of band in either direction, especially on receive only. I'm just not aware of anyone trying anything at all on the VHF radios.

Then, you'd have to get the VCO to lock on every frequency you intended to use. The VCOs in the Spectras involve laser trimmed capacitors, so you're going to have to de-solder the shield, and re-trim those by hand for the target frequency, as well as replace quite a few components to get it to go up that far.

Finally, there's the receive filtering.

Both can be moved up in frequency with a dremel tool and a steady hand.

I think getting it to 220 would be impractical. Someone with a service monitor, the Spectra RSS, a lot of skill and time on their hands could /theoretically/ do it, but I suspect the end product would not be worth the time and money invested.

I suspect you're right, up to the money involved. I think the only significant expense would be in the PA, and it would likely require a complete replacement with a PA module.

Still, I think it would be an interesting experiment to see just how far it can be pushed. All the other bands have proven to be quite capable of getting moved a surprising amount in either direction.

 

[TLF82]

I love 220. Several guys where I live used to use it all the time. Some of them dropped out of the radio world and thus its not used here anymore unless for a repeater link. I sold my alinco 220 mobile (sadly... loved that radio). I still have my yaesu vx-6r and can do weak 220.
I have now moved to 902mhz and Im loving it. (I have a thing for the odd bands)

I for one would love to see more 220 activity. Such an awesome band!

 

[KB7MIB]

Wirelessly posted (Mozilla/5.0 (X11; Linux i686; U; en-US) Gecko/20081217 Vision-Browser/8.1 301x200 LG VN530)

Who makes radios for the Marine band at 216 MHz, and who makes radios for commercial and public safety use at 220 MHz?

 

[fineshot1]

Wirelessly posted (Mozilla/5.0 (X11; Linux i686; U; en-US) Gecko/20081217 Vision-Browser/8.1 301x200 LG VN530)

Who makes radios for the Marine band at 216 MHz, and who makes radios for commercial and public safety use at 220 MHz?

Don't know enough to answer that but i do know that there is some overseas
216 use of that for the marine / maritime usage. Probably either Motorola or Tait.
Also - 220 usage for public Safety overseas.

 

[KB7MIB]

Wirelessly posted (Mozilla/5.0 (X11; Linux i686; U; en-US) Gecko/20081217 Vision-Browser/8.1 301x200 LG VN530)

Both ranges are used here in the States as well. I figured if you can move a VHF or UHF radio up or down to get on the Ham bands, you could do the same with a 216 or 220 radio to get on 222, rather than try to get a VHF up there.

 

[AC2OY]

I programmed in more 220 repeaters in over the weekend....Finding people on them well....LOL

 

[smokeybehr]

California has lots of 220 repeaters, and we have one of the few 220-based linked systems in the US with the Condor System that covers most of the state. I really need to get the old Icom IC37A out and fired up again.

 

[902]

The potentiometers on my IC-37A went bad and had very intermittent operation. Seems like the voltage regulator also goes in them. I also had an IC-47A. These were my favorite mobile radios. A nice little form factor and I prefer the single band radios.

 

[fineshot1]

(I have a thing for the odd bands)!

yes- that would be the same for me and i have a 23cm and 220 repeater both
of which are very robustly made and work very well.

 

[jhooten]

The 220 machine I can get into from the house. The 33 and 23 cm machines require me to get closer to the big city. TOO close for comfort in the case of the 23 cm machine.

I have two handitalkies which give me a total of 5 bands between them, 2 m, 1.25 m. 70 cm, 33 cm, and 23 cm. AND, I can do 10 m FM from a hand held. If only 10 m propagation were a little more consistent.

Don't know what you could mean by oddball bands.