[NLRS] Transverters

[John P. Toscano]

Dan Larson wrote:
> 1) What is the cheapest way to get on 2m SSB? 
> 
> (Really a moot point because I have already ordered the Ten-Tec
> 1210 2m transverter kit to use with my HTX-10)
> 
> Lets see: $90 for the HTX-10 and $139 for the Ten-Tec 1210....
> That comes to $239. That 2m all mode sitting at the candy store
> is going for $259, IIRC.. But I really have two bands in the end
> with this setup (10m & 2m), and I bought the HTX-10 as my
> first HF rig a while ago.

Other than finding a "steal of a deal" on some used gear, I don't think 
you can get in for much less than this.  Even an MFJ 9402 "SSB Adventure 
Radio" is $300 with a microphone, plus $50 for the CW add-in.  And 
though I've heard that this is not a bad little radio, I suspect your 
transverter-based system will seriously outperform it, and be a lot more 
flexible at the same time.

My first "serious" ham radio (after the FM handhelds and mobile rig for 
the local repeaters) was an Icom IC-706 MkII.  I personally think it was 
an excellent investment for me, and don't regret buying it, even though 
it is not the highest performing radio out there.  It got me onto HF, it 
got me onto 6 meters, and it got me onto 2 meters, is convenient, 
travels well, and does what I ask it to do most of the time.  Since it 
predates the MkIIg, it does not do 70cm.  I'm bummed that it receives 
all the way to 200 MHz but they couldn't / didn't squeeze another 25 MHz 
into it (222-225), but a DEMI 222-28 transverter took care of that.  I 
am having good luck with the TIB interface, but I admit that I 
re-engineered it a little bit, and plan to re-engineer it one more time! 
  And I plan to convert my 902 and 1296 transverters to a higher drive 
level and common IF interface, and use them on the IC-706, along with a 
2304 transverter that is already set up for 10 watt drive.  I will keep 
the ALC-based TIB circuitry for the 222 transverter, and extend it 
slightly to limit the 2M output to only 10 watts instead of the radio's 
maximum of 20.  (The newer MkIIg puts out more power on 2M, so it would 
actually be a little less convenient as an IF rig on 2 meters.)  And I 
have grandiose plans for wiring up all the transverters to keep the 
clutter of cables under control, but I need to make the time to actually 
work on all that!

In fact, I must confess that my second "serious" radio is also a 
whizbang jack-of-all-trades, master-of-none radio, the Yaesu FT-847. 
Again, it tries to do so much that it is perfect at none of it, but I 
still like it a whole lot, and am happy to have it.  At the time I 
bought it, it was not a whole lot more expensive than a dedicated 70 cm 
all mode radio I was looking at, and I figured that with all the other 
things it could do, including satellite opeations, it was well worth the 
small extra cost.

My usual contest setup is FT-847 for 6M and 70cm, IC-706 for 2M and 222 
MHz, and for now, a modified Icom IC-251a (split T/R, final PA bypassed) 
for 902 and 1296 transverters.  6 bands, 3 radios, easy to have a liason 
radio available when working a difficult frequency.  As I implied, the 
future configuration will likely be the same (50 and 432 MHz) for the 
FT-847, and then use the IC-706 for the rest: 144 MHz (native); 222 MHz 
(transverter, 28 MHz IF); 902 MHz, 1296 MHz, and 2304 MHz (transverters, 
144 MHz IF).  Seven bands, two radios.  Already have all the parts, just 
need to integrate it all.

If I was starting over again now, and if I wanted maximum performance 
for a moderate cash investment, including saving money by giving the 
soldering iron a workout, I'd seriously consider an Elecraft K2 kit plus 
transverters for every VHF-and-up band I wanted to run.  As others have 
mentioned, 50 MHz, 144 MHz, 222 MHz, and 432 MHz transverters would 
uysually convert to/from 28 MHz, and 902 & up would convert to 144 MHz. 
  You can chain from 28 <-> 144 <-> 902 etc., either using the normal 
full-performance 2 meter transverter, or using a special low-power 2 
meter transverter board that fits inside the Elecraft radio and is 
designed just for driving 902 and up transverters.

Of course, if $$ was no object, I might go with an Icom IC-756 ProII (or 
two of them!) as the IF to the transverters, as that is reported to do a 
very nice job.  Ask Mike (KM0T)!  :)

> 2) From there I want to move on to 432 SSB & 1.2G FM & SSB
> So whats the cheapest way there, considering that I have 
> good building skills & have done some homebrew for HF?
> (I wield a soldering iron skillfully because I've had one in my hands
> since I was 10 !)

I'd suggest 6 meters next, 432 after that, 222 after that, then 1296 and 
902, based on how much fun you can have in the contests with the various 
bands.  Check the "band analysis" that I did for the ARRL 2002 contests 
on the NLRS web page:
   http://nlrs.dropboxone.net/BandAnalysis-2002-ALL.htm

Transverters are "the only way to go" in my opinion for 222 (almost no 
single-band all-mode radios available), or for 902 and up.  On the 
higher bands, there is a big issue with feedline loss.  If you can get 
the transverter close to the antenna (and protected from weather), your 
performance will be far superior to a radio down in the shack and a long 
run of coax up to the antenna.  Even though I don't have a tall tower, 
the total run of feedline from the top to my shack is nearly 100 feet. 
My 902 and 1296 transverters are about 20-25 feet from the antennas, and 
the rest of the feedline run is at the IF frequency, where the losses 
are essentially not important.  On 6M and 70cm, I like the convenience 
of the multi-band FT-847, and have good luck with those bands in that 
radio, but the K2 plus transverters would doubtless knock its socks off.

> I'd really prefer to build transverters for these bands, but, by the
> time I buy the 432 & 1296 transverter kits from DEM, I have spent
> enough money to just go buy an FT-857 and I'd have 2m & 70cm
> taken care of & be happy until I wanted to go up to 1.2G or higher.

I'd probably go for the IC-706 MkIIg instead of the FT-857, I find the 
slightly bigger size is worth the convenience of better front panel 
controls and displays.  (Of course, the FT-847 is bigger, and easier to 
control in many ways, but the size jump is considerable there, as is the 
price jump.  I've used the FT-847 mobile under special circumstances, 
like contest roving, but the IC-706 is about as big as I'd want to go 
for 'everyday' use mobile.  I personally think the FT-817 and FT-857 are 
smaller than I would want to use, but that's a personal preference.)

There are radios with 1.2 GHz band options (e.g., the Kenwood TS-2000, 
Icom IC-910H), but I think that their prices are rather high for the 
level of performance you would get compared to a 23cm transverter.  They 
*DO* cover the entire 1.2 GHz band, however, so if you are planning on 
both satellite and terrestrial 23cm operation, there is an advantage 
this way.  I have one transmit converter for 1268-1272 MHz satellite 
use, and a full transverter for 1296-1300 MHz terrestrial use.  (Plus a 
2400 MHz receive converter for the satellites and a full transverter for 
2304-2308 MHz terrestrial use, but that's another story.)

> Cheaper kits, homebrew plans (as long as parts can be had), 
> and even converting/hacking surplus & junk electronics are all
> possibilities I have been considering

Some other sources, most of them *NOT* cheaper kits...

W1GHz 222 transverter, designed to nicely complement the FT-817 (or, I 
guess, the FT-857, which is similar in appearance):
   http://www.w1ghz.org/222xvtr/222.htm
I'm tempted to add one of these ~ $100 kits to an IC-706 MkIIg and have 
the four lower VHF/UHF bands all together in a compact package for 
everyday mobile use, and to simplify setup for roving (just add the 
microwave bands, PA's, and steerable antennas, etc.)

Elecraft 6M, 2M, 222 MHz transverters (to 28 MHz IF) designed for the K2 
but adaptable to other rigs.  Too bad, no mention of a 70cm model yet.
   http://www.elecraft.com/XV/XV.htm
These transverters are brand new to the market, and I don't know if they 
have gone head-to-head against any of the more mature market offerings. 
  But Elecraft's reputation is excellent, so I'd be shocked if their 
performance was anything less than excellent.

SSB USA -- their own line of transverters, plus the DB6NT models
   http://www.ssbusa.com/ham.html
These tend to be a premium in price (*and* a premium in performance), 
compared to the Down East Microwave gear that many of us know and love.

Other kits (some unbuilt, some part-built and/or in need of repair) can 
be found if you look hard enough.  I haven't, but KC0LBT has...

> 3) Are there any caveats having a daisy chain of two or more transverters?
> HTX-10 -> 10m/2m xvtr -> 2m/70cm or 23cm  xvtr ?

Mainly matching the drive level of the middle transverter's output, and 
controlling the gain of the middle transverter's input.

Down East Microwave makes a few 144 <-> 28 transverter board that are 
explicitly designed for the purpose of converting a microwave 
transverter with a 2 meter IF to an HF radio.
   http://www.downeastmicrowave.com/PDF/144-28ECK.pdf   (for Elecraft K2)
   http://www.downeastmicrowave.com/144dc.htm           (for general use)

These have very low power output and very low receive gain, which is 
perfect for an intermediate conversion.  The final transverter needs the 
higher power and the low noise/higher gain receiver front end.

But you *CAN* use a standard 144 <-> 28 transverter in the middle, you 
just may need to slip some attenution in line.  Fortunately, loss is 
always easier to make than gain.  :)

Folks around here are mostly using 144 Mhz IF's for all the bands from 
902 MHz to 24 GHz, but I have heard of some folks using 1296 Mhz as an 
IF for the 10 GHz and up microwave bands.

Hope that helps some.
Good luck, and enjoy the higher bands -- I sure do, when I find (or 
make) the time to get on the air!

73 de W0JT