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Reviews For: ICOM IC-706 - All flavors

Category: Transceivers: HF Amateur HF+6M+VHF+UHF models - non QRP <5W

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Review Summary For : ICOM IC-706 - All flavors
Reviews: 426MSRP: IC-706MKIIG
Ultra Compact HF/6 Meter/2 Meter/440MHz Transceiver
Product is in production
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# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
OK9DMR Rating: 2023-07-11
Icom 706MKII "Good" Time Owned: more than 12 months.
Icom IC-706MKII KV (100w ) VHF (20w)
I am satisfied with it, the station is very small and handy that it almost fits next to the computer monitor.
The only thing that satisfied me is that the 6m - 160m and 2m bands can even be tuned to the 50 - 80 MHz band
blocking and it is possible to listen to the aviation bands 118 – 135 Mhz. And the rest Radio radio station FM transmitter .Supports all Modes AM,FM,NFM,WFM,CW,USB,LSB,RTTY,
US7IGN Rating: 2023-03-23
Excellent portable radio! Time Owned: more than 12 months.
Another vote for this wonderful radio. I have been using my IC-706MK2G outside of the shack for over 10 years and am very happy with it. It is hopelessly outdated, but it does its job perfectly. If you make the screen backlight smaller, then the current consumption is less than 1A. It is a little heavy, but exceptionally durable. I have both narrow CW and SSB filters installed, I added surge and reverse polarity protection, protective handles and made some modifications. This is the last radio I would sell if I needed money. Also, during this time, an analogue with better characteristics did not appear.
W9MT Rating: 2022-07-12
Balanced performance for base or mobile use. Time Owned: more than 12 months.
July 11, 2022 update:

All 3 radios in the 706 series use two small SPDT relays in pairs to switch sections of the BPF sections in or out for the band of interest. My problem was the 3.5 band filter section. It could be either of the two relays causing my problem.

I could make the problem go away for about an hour by heavily cycling PTT until the chatter became less and finally worked like it should. Wait an hour and the problem would return. This pointed squarely at the relays. It was a crapshoot whether it was the input relay or the output relay. This is where my bigger problem started.

The relay type used in the Mk2G's BPF board was slightly larger and had a different footprint than those used in the Mk2/non-G radio. However, the older relay type was available on eBay from China, and the newer type has been obsolete and NLA since 2019. (Rats !!!) So I bought five of the non-G radio's relays and cobbled one in with short lengths of Kynar wire-wrap wire.

I carefully reassembled the BPF board back into the radio, taking great care to assure everything, including the flex cables and coax cables were properly mated and everything fit nicely.

Now I didn't have an intermittent 3.5 band. Instead PTT didn't work on any band. HF through 6 did not transmit at all. Years of experience and my instincts told me I likely fractured a runner in one of the flat flex cables during multiple removals and insertions, with my likely breaking a control line near the end of one end of the cable common to PTT control for all of the HF/6m bands.

I was frustrated and (surprise!!!) no longer having fun. So the radio got sold cheaply as a non-transmitting radio with a "still great" running receiver. My faithful friend of 22 years (bought new at Dayton in 2000) was sold as a parts donor radio. The cosmetics were great. The control head was mint. The buyer got a smoking deal (figurative smoke only).

I still have the Mk2/non-G that I brought back from the dead and it works at proper factory specs for that generation radio. Come the time it ultimately winks-out, I'll likely do the same as with this radio. But for now it's my dedicated FT-8 radio. So, the fun is still there...and I still like 706's. Maybe, just maybe, it will be many years before that radio bites the dust. I certainly hope so.

August 2, 2021 update:

The IC706Mk2g I purchased new at the Hara Arena Dayton Hamfest in May 2000 has finally caused me its first "hint of trouble" after more than 21 years of stellar service.

I use this radio to work FT8 mode with a Signalink USB soundcard interface. It works great with WSJT-X and GridTracker software. I used 40m for most of my FT8 work and decided to try 80m. On 80m transmit didn't work correctly yesterday. I could hear the Mk2g's BPF boards relay chattering, making transmit intermittent. A tap on the radio calmed it down but this was temporary. Today it acted up the same way.

I disassembled the radio, suspecting the flex cables to the BPF board developing oxidation or corrosion issues. While the connectors on the board have a gold flash on their contacts, the flex cables are simply tinned. I cleaned the ends of the flex's with a cotton swab dipped in isopropyl alcohol. One flex made the swab head a bit dirty. Carefully replacing the flex's and coaxial cables that needed to be reinserted, I screwed down the BPF board and reassembled the radio's covers.

It now works without issues and a solid TX on 80m and all the other bands.

Moral of the story...suspect mechanical contacts before digging any further. Fortunately I didn't have to dig into the relays. It was only a contact problem with the flex's and their mating connectors. Problems like this date all the way back to the Radio Shack TRS-80 Model 1 computer's connection to its expansion interface!!!

I still like my two 706 series radios, a WHOLE lot.

Original review:

I own two examples of this radio. My first was an IC-706Mk2G that I bought new at Dayton in the year 2000. The 2nd is an IC-706Mk2 that was purchased as a tech-special basket case at the "late" Williams Arizona hamfest back in 2014 or 2015 (the last year this fest was held).

The Mk2G has never caused me a hint of trouble. I fitted it with the 1.9KHz (FL223) narrow SSB filter and the 350Hz (FL232) CW/RTTY filter. I believe these two filter provide the best balance of performance on receive for the modes for which they are intended. I do own an FL100 500Hz filter that I bought on eBay for about $50, just to see how it compares with the 350Hz unit. I don't like it as much. It tends to really ring on receive. I'm told the 250Hz does not do that, but I have no personal experience with it.

It is true that VHF/UHF multimode operation is a bit of a compromise with this Mk2G radio. No, it won't work as well as a radio intended for 10m to "blue light" operation (e.g.: FT-847). But 706 series radios do work, and well enough to wet your feet to see if you want to acquire radios more optimized for VHF/UHF weak signal work. Others have complained about the CTCSS encode performance. ALL VERSIONS of the 706 series have a design problem with subaudible "PL" tone encode level. It's set with a resistor feedback gain pair across the op amp that injects this tone onto the audio path...and it's set TOO LOW. (There is NO PL-level adjusting pot.) Typical deviation levels will be found to be 200-400Hz with the fixed amplification settings across that op amp. (It's a differently part numbered one on each version of the 706 radio series, but the circuit configuration is the same.) If you solder another chip resistor across the input resistor to make the gain higher (I used 1 MOhm.) You'll get something in the sweet spot between 700Hz and 1KHz of subaudible tone transmitted. That's enough to open and keep open the tone squelch of your target repeater. I used a leaded 1/10th Watt resistor on one of these upgrades. It looked like a giant log with fire hoses coming out of both ends. Use a dab of RTV holding the resistor body to the top of a nearby surface mount IC and you won't mechanically stress any solder connections.

The Mk2G also had a bit of RF interference with my external LDG tuners. This can be tamed with using a shielded cable between the two Molex connectors on the tuner and radio.

When mobile, the Mk2G also seemed to have a feedback loop getting RF into the microphone speech amp's, but only on 40m sideband. Winding about 8 turns of the mike's coil cord around one of those brute force square ferrites fixed this problem. (It was amusing that the mike for the basket case Mk2 already had its mike cord wound 8 times around a large circular toroid coil form. I already knew why....)

So, my Mk2G was a great unit to buy and I still use it as a backup radio at my IL QTH. It easily drives a Gonset GSB-101 (4x 811A) amplifier to 700-800W dead carrier.

The Mk2 was bought with the radio not powering up nor the 2m band receive not working at all. It was a puzzle I wanted to solve and it took me several months worth of evenings to sort things out.

The power up problem was due to Icom using foam backed tape between the PLL board and the chassis to prevent shorting of componentry to ground. After about 10 years worth of heat and humidity, the adhesive eats thru the solder resist of the PLL board and then proceeds to open the copper runner that carries the "goosing signal" from the front panel power switch to the Main Board (where the processor lives). Icom Service in Belleview WA was useless in providing guidance on how to fix this. I jumpered a length of Kynar wirewrap wire from the connector where the signal comes into the PLL board and found a topside thru-hole on the Main Board on the same circuit node as the processor's goosing pin.

Viola!!! The radio now powered up and was working great on 160 thru 6 meters. 2m was still a problem.

Here's where things get really interesting. 2m transmit and receive were 15 KHz apart. There is a pot that zeroed them back on top of each other. Receive was still very, very deaf. I suspected the preamp (very necessary on 6m and 440 on the Mk2). Icom Service was very useless again and further informed me that replacement parts were NLA from them. So, I was on my own.

Figuring that the problem was one or more of four part types in the preamp, I did an internet search and found that these generic parts were available from a Hong Kong company on Amazon !!! So, I bought five of each when I only needed one. (A wise move if you've never worked with SMT that small.)

I learned very quickly that this kind of work needed 1)a lot of time, 2) a steady hand, 3) "ant burner" magnifying visor, and 4) lots and lots of illumination. I replaced the parts and the radio's receiver sprang to life.

Then I made a mistake. Probing around to assure everything was as it should be with a VOM probe, I accidentally shorted a probing point to a shield and saw a spark and let some smoke out of a component somewhere. Deafness returned.

I tried replacing all of the 4 part types again, to no avail. I finally realized two things. I blew an RF switching diode with my probing. (Radio power was turned OFF at the time, but the 706 series still has Vcc applied to the output board when powered down. So to TOTALLY kill power, for real, you have to remove your DC power supply's connection to the radio. Replacing the 4 part types was not necessary EITHER TIME. I really didn't need them at all, it turned out. There was simply BAD FACTORY SOLDERING in the 2m pre-amp circuit.

So, by replacing the switching diode, everything was working again. Receive on 2m is back to original spec's...not as good as for a single band FM 2m xcvr, but "good enough" and multimode, too.

BTW, the same CTCSS level mod needed to be done to this radio, too. There's another 1MOhm resistor in the op amp circuit in this one too.

My Mk2 is fitted with the same 1.9KHz and 350Hz IF filters as my Mk2G. I love both radios. Both are keepers.

The only thing I don't like about them is the DSP board both of them have. The ANF function works great on carriers, but the DSP noise reduction stinks. By the time one turns the attack level high enough to do decent noise reduction, the audio pumping and weird DSP artifacts make the voice sound very unnatural.

So I run both of my radios with an external audio DSP device. A standard ClearSpeech Speaker works great. So do the BHI DSP boxes. These make the 706 series radios a joy to operate without the annoying hiss and white noise that makes many weak signals uncopyable.

I applaud Icom for the cleverness of integration in the designs of their 706 series radios. Sure, they made some faux paus, but these are easily fix-able, given some time and patience.
N1UMJ Rating: 2020-11-02
A real work horse! Time Owned: more than 12 months.
I had an IC-706MKII for a short time and liked it but sold it. In 2005 I bought a IC-706MKiiG for portable, or backup in the shack and it's been to numerous special event stations with me, vacations, moves, temporary stay overs between moves, it's done a lot and is still going strong. Now, ready to go HF mobile, and not wanting to break the bank, I bought another one. For what it is, small shack in a box, geared toward mobile use, it's great. Playing with other radios, it's easier to use than many in the same category, I get good reports with it, and though they get warm, I stuck a couple optional filters in them and they serve their purpose extremely well. Not many radios have stayed with me over 15 years, I've had a lot in that time and though I missed some and bought more I don't think I ever had 2 of the same radio at the same time except now this with one portable in my go box and the other mobile.
WB4IVG Rating: 2020-09-13
One of the Best radios that I have ever used! Time Owned: more than 12 months.
I own 3 of these radios all 706 MK2Gs I have owned the older versions also but these radios have a permanent place in my station. I use one Mobile, another for Portable Camping and such, and the third for just use on my workbench as a general-purpose Receiver and RF Source! I have the additional filters in 2 of the radios and the DSP unit in all of them. The only Negatives I can find are the Lack of the 220 MHz band and the inability to make any adjustments to the Noice Blanker! It would also be nicer to have easier access to the DSP Settings. All in all the only other 2 radios that even come close to this radio are the Icom 7000 and the Yaesu FT897D but like this radio, they also have a couple of minor short comings. This is one FANTASTIC RADIO!
W0BKR Rating: 2020-09-13
Great Radio even for Today Time Owned: more than 12 months.
I have the MK2G and a well packaged radio for HF, 6, VHF, UHF. You can't go wrong with this package. Fairly reliable and easy to understand use.
WB0RXL Rating: 2020-09-08
Great Mobile Rig Time Owned: more than 12 months.
Actually have two of these. One in the car for HF mobile operation. Receives well on all frequencies and on 40 - 10 meters transmits well. On 80 meters - well one just needs more than 100 watts to be heard by anyone. Very rugged rig that is stable even on back country roads. The unit is mounted in the trunk with the extender cable to the face plate in the center console.
No complaints at all when used as a base station.
Great radio.
K7UV Rating: 2020-02-18
ICOM IC706 Plain Vanilla Version Time Owned: more than 12 months.
I've owned my IC706 for over 20 years...purchased used. The radio works well on CW, SSB & Digital. I've had great reports about it. Lately I've used it mainly for FT8 & WSPR without any drift on 160 through 15 meters. I don't know about higher frequency bands though. The receiver is good on all bands, including 2 meters. On six meter mobile, I've worked many states using Es. It went dead on me once and it turned out to be a fuse that *jiggled* out of the fuse holder. I compressed the fuse holder, reinserted the fuse and no problems since. It probably fell out of the fuse holder from vibration in the trunk of the car. The separation kit works fine. Ive had no problems, other than the fan being a bit noisy during transmit and I've thought of modifying it so the fan runs continuously at a slower speed. During mobile, I never noticed the fan, so it isn't too bad at all. It's a do-everything radio, stable and tiny by HF rig standards. It's been a real workhorse on all bands including 160 meters, 60 meters (someone modified it before I purchased it) and all HF bands.
KF4KQS Rating: 2019-11-04
MkiiG Time Owned: 6 to 12 months.
Used one for a time while I was an OTR truck driver. Antenna system for HF was a short Hustler mast system with a set of resonators, VHF/UHF was an MFJ 3/8 mount dual band whip. Had a lot of great DX and local contacts with that radio. It stood up very well to the bumpy ride up in the cab of that truck and never once failed. It’s a shame Icom had to stop producing these radios.
SQ2TAC Rating: 2019-11-03
Good equipment for home and outdor Time Owned: more than 12 months.
Hi there! I've had ic706mk1 before, and now I use ic706mk2G. Both of them are very good TRX for partly home/mobile usage. However power consumption is quite big - 2A on RX comparing to FT857 which is 0,7A. In RX and TX quality both ic706 and ft857 they are pretty much the same. In my opinion Icom's buid quality is a bit better and I like menus much more than in FT857. IC706MK2G is not the best radio ever, but i like it. I would buy it again:-)