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Author Topic: HF Transceivers for MARS  (Read 28921 times)

AE6OX

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HF Transceivers for MARS
« on: December 12, 2003, 01:44:19 PM »

I am currently an inactive ham but hope to reconstitute my station and return to the airwaves soon.  I am interested in MARS and wondering what amateur HF tranceivers would best suit both my amateur interests (CW/digital) and MARS use.

I have seen mentioned, for example, that the bandpass filters built into some modern solid-state amateur HF rigs significantly attenuate output when operated far outside amateur bands (manufacturers' "official" MARS mods notwithstanding).  Also, that some solid-state PA stages don't take kindly to non-amateur bands.  

Perhaps the best solution is to seek a separate older or "no frills" rig as a dedicated MARS transceiver?  Any opinions and wisdom from experienced MARS hands is appreciated.

73,  Bob AE6OX (ex-K6LDX)


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K3WVU

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HF Transceivers for MARS
« Reply #1 on: December 12, 2003, 10:02:04 PM »

Bob,

I'm active in Navy/Marine Corps MARS and I have two ICOM rigs, an IC-718 and an IC-706MKIIG.  Both were very easy to 'open up' and they operate well on all frequencies (unlike the ICOM 'Pro' series).  I also have a Yaesu FT-100D in the car that I modified, and it does very well also.  If you want a cheap, dedicated HF rig for MARS, the 718 might be it.  There is only one potential problem with the 718, according to the ARRL review I read.  The transmit/receive 'turnaround' or 'recovery' time is too slow to operate well in the 'burst' modes, such as PACTOR, G-TOR, AMTOR-ARQ, or CLOVER.  That's not a problem for me operating in the Northeast, because we primarily use AMTOR FEC for passing traffic (our 'traffic rep' uses AMTOR ARQ to retrieve traffic from the switch, however). ICOM supposedly has a mod to fix the problem, or perhaps they have fixed the problem on later model 718's.  Also, CW isn't used in MARS anymore.  The ICOM 706 doesn't have the same problem with turnaround time and , of course, could also be used on MARS VHF/UHF repeaters as well.  You might want to check with the state director of the MARS service that interests you to see what modes are used in your area.  I'd recommend going to http://www.navymars.org to get started.  If I can be of any help, let me know.

73

Dwight NNN0TPR/NNN0ASI Eight
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KB9ZB

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HF Transceivers for MARS
« Reply #2 on: December 13, 2003, 12:10:21 AM »

Well in nut shell mosty all newer radios have a fairly easy mod that will work fine for mars and ham activity ( just note that when the mod is made it will trasmit asmost anywhere, so when haming you will have to keep a close eye on the frequency limits of the ham bands)
If you are looking for a rig that wroks very well for mars/ham activities and does digital off the acc jack in the rear without any other gear required, loom at the kenwood line. they atre very easy to mod and will do usb digital off the rear, icaom and other do have an issue with that in most but not all models.
ron
nnn0vag navy marine corps mars
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KG4RUL

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HF Transceivers for MARS
« Reply #3 on: December 13, 2003, 01:55:45 AM »

I use a Kenwood TS2000 with a Force 12 Flagpole Antenna for base operation.  I have to use an external antenna tuner as the built-in tuner doesn't have enough range to tune up 86 meters.  I really appreciate the IF DPS capabilities of the TS2000 for this type of operation.  

For portable ops, can take this radio and tuner, along with a G5RV dipole, deep cycle batteries and my Honda generator, into the field.  I can operate this configuration for 72+ hours on 5 gallons of fuel if need be.  

I also have the luxury of being able to monitor MARS VHF frequencies while operating HF using the TS2000 sub-receiver capabilities.

Dennis - KG4RUL
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N3ZKP

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HF Transceivers for MARS
« Reply #4 on: December 14, 2003, 11:02:24 AM »

Bob,

Two very good rigs for MARS use:
Kenwood TS-570 and Alinco DX-70TH. The latter qualifies as no-frills. :)

Seriously, I use a 570 and two DX-70s (one portable, one mobile) and have no problems on any HF MARS frequencies. Antennas run from a Butternut HF-6V with a LDG AT-1000 antenna matcher for home use to a High Sierra motorized antenna mobile and various wires for the portable rig.

Lon NNN0OOR / NNN0GAW THREE
Baltimore, Maryland.



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KL0S

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HF Transceivers for MARS
« Reply #5 on: December 17, 2003, 12:49:49 PM »

For those who may have been considering the new TenTec Orion for an HF rig be advised that there is little if any out of band capability for MARS operation. TenTec's answer to my query was:

At 10:36 AM 12/17/03 -0500, you wrote:
>Can you tell me what the current outside the ham band capabilities are for
>the Orion?  When I asked at Dayton last year I was told that there would be
>no operation outside the ham bands....recently I heard a MARS member remark
>that new firmware had been released that allowed at least some operation
>beyond the band edge, specifically immediately above 4 MHz.

The top end of the Orion is 4.010 so may not help you much.  There is no
plans for the Orion
to be modified from its current frequency coverage at this time.

73,
Stan Brock, WD0BGS
Amateu Radio Sales
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WA7H

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HF Transceivers for MARS
« Reply #6 on: December 30, 2003, 12:37:39 PM »

I've been in AF MARS for over 20 years and have used a Collins KWM-2A, Drake TR7, Yeasu 757GXII, ICOM IC-706MKIIg, Kenwood TS-B2000, Yeasu FT-857, and a Ten-Tec 550 Pegasus. They all seem to work well on MARS frequencies as well as the Ham bands. They all require some form of modification though from just changing the crystals in the Collins to removing a diode in the Icom and Kenwood to flipping a micro switch inside the 757. As with ham radio the right rig depends on what you want to do with it and how much money you want to spend. If your primary operating mode is digital I would suggest the Pegasus or TS-B2000 (TS-2000). If it's SSB then any of these rigs will do nicely. If you primarily want to operate mobile or portable at a reasonable price take a close look at the IC-706MKIIG or the FT-857, though once you add up all the accessories you may pay as much as the TS-B2000. Whatever radio you decide on ALWAYS contact the manufacturer and make sure it can be easily modified for MARS operation before you buy it(they always ask for a MARS license before releasing the technical information). Ten-Tec will even do the mod before shipping the radio to you. For the other manufacturers you will have to find an electronics technician or do it your self. If you plan to use a general purpose multi-band antenna like a G5RV you will need an antenna tuner. The TS-B2000/TS-2000 has a built in antenna tuner but needs a close matched antenna to work well. There is an internal antenna tuner available for the Pegasus from LDG that works great and will tune a 10:1 SWR antenna. Half the fun is shopping for the radio!
Steve/wa7h/afa5si
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WD8WV

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HF Transceivers for MARS
« Reply #7 on: January 06, 2004, 02:38:11 PM »

I use a Yaesu FT-840 (very simple to mod).  The mod does not consist of any desoldiering or cutting of wires or circuts.  I will not go into specifics but you basically put a jumper wire from the case to a pin and turn the radio on while pushing some additional functions to get into a menu and just turn it on.

I also use a Heath SB-1400.  This rig required the cutting of a wire to get it opened.

Both rigs work flawlessly on MARS frequencies anywhere in the spectrum, and work on 5 MHz.

I also had an Alinco DX-77T.  This one called for desoldiering a pad.  Once done it work flawlessly too.

It seems to me that if you have one of these new modern rigs with DSP filtering and such is where you will find problems.  Rigs of 5 and 6 years ago will probably work fine.  That is why I like it simple, not a lot of extra features, that I probably won't use, and not a lot of menus.  

73
Juddie KC8CON/AAT3EM
WV Army MARS
http://www.qsl.net/armymars/wvarmymars.thm
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KB9ZB

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HF Transceivers for MARS
« Reply #8 on: January 06, 2004, 09:45:20 PM »

I am interested in your use with data, does it still have the issue of defaulting to lsb when using the accy jack or have they resolved this? I am intersting in purchaing one of these for use o\in ouir art team.
ron henry
nnnovag
Navy MARS
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K8CAV

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HF Transceivers for MARS
« Reply #9 on: February 19, 2004, 12:02:17 PM »

I've been using a Kenwood TS-570S modified for MARS (out of band) operation and it has full power output  at all of the MARS frequencies I've used over the last two years. It works well and I've been very happy with it.
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N2CKH

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HF Transceivers for MARS
« Reply #10 on: February 25, 2004, 02:18:05 PM »


Hello All,

There are many key factors if you are shopping for an HF transciever with respect to MARS operations as we are now making use or more frequencies that do not straddle the edges of the Amateurs bands and newer digital modes.

1. The ability for the radio to operate at all frequencies between 2-30Mhz at full output and a clean signal is needed. Full built-in automatic antenna tuner performance if the radio is so equipped is also required. So existing makes/models fall short on this.

2. Transmit/Receive recovery time: This is critical for the use of digitals modes and especially with the use of Automatic Link Establishment (ALE).

3. Wide Bandwidth Selection: The day used to be that a 2.4khz or less SSB bandwidth with the way to go, that being needed for receive capability on our crowded Amateur bands. However, for ALE operation we need a wider bandwidth now, 2.6Khz for 16 tones and 2.8Khz for 39 tone ALE. Thus the addition of a 2.8Khz filter from the likes of INRAD etc. or IF DSP is needed here.

4. A nice feature, would be full radio interfacing
for external TNC's and PC sound card digital solutions where the radio provided all the points of connection and automatic switching between microphone and modems. Some manufacturers have attempted to address this with Accessories ports (ACC) to some
extent, but have fallen short of real success.

Sincerely,

Steve Hajducek, N2CKH/AAR2EY NJ


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KB3DMY

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HF Transceivers for MARS
« Reply #11 on: May 06, 2004, 11:16:59 PM »

   Hi all I have just sent a e-mail to join MARS Navy/marines all I have is a HTX-242 that can be set to transmit/recieve MARS/CAPS would that make for a good MARS/HAM rig? it will be just a TEMP thing until I can get enough money and reseearch the rigs I want/need for HAM/MARS use.


Thanks
Kevin KB3DMY 73
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N3ZKP

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HF Transceivers for MARS
« Reply #12 on: May 07, 2004, 12:27:32 AM »

Kevin,

There is very little Navy-Marine Corps MARS activity on 2m. At best there is some small amount of local use. I know of no actual nets in this region that are conducted on either 2m simplex or repeaters. There certainly is none here in Maryland.

You need to be HF capable. That does not mean you have to have an amateur license granting HF privileges. It means you must have an HF rig capable of transmitting on the MARS frequencies, the majority of which are just above and below the amateur bands. The MARS license grants you HF privileges on MARS frequencies.

The best thing to do is contact a local MARS member and let him fill you in, or you can feel free to contact me via e-mail and I will be happy to assist you.

Lon NNN0OOR MDE
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NW0LF

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HF Transceivers for MARS
« Reply #13 on: June 02, 2004, 11:27:56 PM »

In the mobile, I use an ICOM 706 with an Outbacker Perth with 2nd stinger for MARS frequencies which works well.  I will be setting up a base  station consisting of an ITT Mackay MSR8000 with power supply and autotuner with approx 100  feet of wire.  I also have a Kenwood TS940SAT that I opened up that will end up with a dipole for MARS and a vertical for Amateur HF.  

Tom K9WLF/AAV4SA
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W6SGJ

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HF Transceivers for MARS
« Reply #14 on: August 12, 2004, 09:38:31 PM »

I read your comments about using your TS-570S for out-of-band operation.  I just bought a TS-570S(G)and want to modify it so I can operate the 60m band.  Can you tell me how to make the mod for out-of-band operation?

TNX es 73,

Dick ... W6SGJ/7  Vancouver, WA

dgeordan@aol.com
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