Tag Archives: Icom

How to effectively disable transmit on the Icom IC-7300 via Settings menu

Many thanks to SWLing Post contributor, Justin (N2UJZ), who shares the following Icom IC-7300 tip:

I was looking for a way to completely disable the TX (to share an antenna) on a IC-7300 and found this article. I didn’t get any answers saying “yes” but I just figured it out and yes it can be done.

Press ‘Menu”, then press “Set”, then “Function” to bring up a menu starting with “Beep Level.” The fourth item down is “Band Edge Beep.” You want to set that to “ON (User) & TX Limit”

Then once that is turned on, there will be a “User Band Edge” option in the Function menu. Under that select and delete all of the band edges. The radio will now not TX at all from any button on any band. To re-enable TX, change the “Band Edge Beep’ anything other than TX Limit.

[IMPORTANT] Don’t forget to save to the SD card before deleting the band edges or you might have to re-enter them.

I was just disconnecting the mic until today but this way I’m a little more at ease now with the 7300 sharing an antenna with the HackRF. 73, Justin N2UJZ.

What a brilliant tip, Justin. Thank you for sharing this!

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Portable tuner (ATU) options for the new Icom IC-705

Many thanks to SWLing Post contributor, Paul, who asks:

What are good choices for ATU and 100W amplifier for the IC-705? [Also] will the Icom AH-4 antenna tuner work well with the IC-705?

Great questions, Paul!

100 Watt Amplifiers

I’ve limited experience pairing the IC-705 with external 100 watt amplifiers. I own the Elecraft KXPA100 and it pairs well with the IC-705 via RF sensing. My hope is that SWLing Post readers may be able to chime in here and offer more suggestions as there are a number of inexpensive, basic, amplifiers on the market now but I’ve never personally used or tested them. I can say that the KXPA100 is a beautifully-engineered amplifier.

Antenna tuners

Icom AH-4

First off, regarding the Icom AH-4 ATU, I’m not certain if the IC-705 has the same control commands as the AH-4 (I’m guessing it does, but perhaps someone can confirm–?).

It would not be my first choice as a portable antenna tuner for field work. For one thing, it’s a pricey at $300. That, and I’ve always viewed the AH-4 as more of a remote antenna tuner for those who need a permanent matching box outside the shack near the antenna feed point. For that application, I’m sure it’s amazing.

According to the AH-4 specifications, it requires “10 W (5–15 W)” of tuning power. I’m not quite sure what the “5-15” watts means, but the IC-705’s max output power is 10 watts using an external 12-13.8V battery, and only 5 watts using the BP-272 Li-ion Battery. Not sure if that would be adequate to trigger the AH-4 to find a match without some sort of command cable connection.

For portable ATUs, let’s take a look:

IC-705 Portable ATU Options

The Icom IC-705 actually has a port on the side of the radio that allows one to connect the rig to an ATU for some level automatic ATU control. At time of posting, there are two ATUs in the works that are able to use this port: the Mat-Tuner mAT-705 and the Icom AH-705 (there could be more, but I’m not aware of them).

Mat-Tuner mAT-705 ($220 US)

I reviewed the mAT-705 on QRPer.com (click here to read). In short, it’s absolutely brilliant at matching antennas quickly and efficiently, but it has a few design shortcomings. The main issue is that you must use a mechanical switch to turn it on and off, else you deplete the internal 9V battery within a week. Most similar ATUs either have auto-off functionality, or at least an external power option. Since the mAT-705 can connect directly to the IC-705, it automatically knows when you need to tune to a frequency and will do this anytime you send a carrier, hit PTT, or initiate tuning via the menu option. It can also remember frequencies you’ve already matches to make the process quicker. The mAT-705 is also RF-sensing, thus can work with other radios. Vibroplex is the US distributor of the mAT-705. Note, too, that there are a number of portable Mat-Tuners that will work with the IC-705–the mAT-705 is the only one that uses the IC-705 control cable (which I feel is actually unnecessary).  Check out their full product line before ordering.

Icom AH-705 ($T.B.A.)

The Icom AH-705 is Icom’s own external ATU designed to work with the IC-705 and fit in the LC-192 backpack. Since the AH-705 will be able to connect directly to the IC-705, its functionality will be very similar to the mAT-705. I’m speaking in future tense here because, at time of posting (18 November 2020), the AH-705 is not yet in production and we’ve no retail price. With that said, Icom has a legacy of making fine ATUs, so I’ve no doubt it’ll function well. Like the mAT-705, it has a mechanical on/off button so you may have to be aware of turning it off when not in use to preserve the internal alkaline batteries. Unlike the mAT-705, it has an external 13.8 VDC power connection. Universal Radio will update their site with pricing and shipping information once available.

Elecraft T1 ($160-$190 US)

The Elecraft T1 ATU has been in production for many years now and is a fabulous portable ATU. Not only is it incredibly adept at finding matches, but it’s also efficient in terms of power usage. It will run for months on an internal 9V battery (that’s very easy to replace in the field). The T1 has no special connection for the IC-705, but it does have an optional T1-FT817 adapter for the Yaesu FT-817 series transceivers. In truth though? I find control cables unnecessary because tuning the T1 only requires pressing the tune button on the ATU, then keying the transceiver. Once it finds a match, it shuts down and locks it in. You can purchase the T1 directly from Elecraft ($160 kit/$190 assembled). The Elecraft T1 is my portable ATU of choice.

LDG Z-100A ($180 US)

I’ve owned a number of LDG tuners over the years an absolutely love them. I find that they offer great bang-for-buck, perform amazingly well, and are built well. In fact, I designed an outdoor remote antenna tuning unit around their original Z-11 Pro auto tuner. It’s housed in a sealed waterproof enclosure, but is completely exposed to outdoor humidity and temperature changes (which can be dramatic here on the mountain). I’ve been powering the Z-11 Pro for 10 years off of a discarded sealed lead acid battery that’s being charged by a Micro M+ charge controller and 5 watt BP solar panel. I’ve never needed to maintenance it. One of LDG’s latest portable ATUs is the Z-100A. I’ve never used it, but I imagine it’ll perform well and I may very well reach out to LDG and ask for a loaner to review with the IC-705. It does have a command cable port that works with Icom radios, but I’m checking with LDG to see if it works with the IC-705 (I’ll update this post when I hear back). The LDG Z-100A retails for $180 via LDG’s website.

Emtech ZM-2

Shortwave radio listeners, especially, should take note of the Emtech ZM-2 balanced line tuner! Unlike the ATUs above, the ZM-2 is manual–meaning, you manually adjust the tuner’s L/C controls to achieve a match with your antenna. I’ve owned the ZM-2 for many years and have used it with a number of QRP transceivers. Since it’s not automatic, it might take a minute or so to find a match, but it’s worth the wait. The ZM-2 requires no batteries to operate, which makes it an invaluable and reliable little tool in the field. In addition, since the ZM-2 doesn’t require RF energy in order to find a match, it’s a brilliant choice for SWLs who want to tweak their wire antennas. I find it functions as well as if not better than other manual tuners designed specifically for receivers. The ZM-2 is also the most affordable of the bunch: you can purchase a pre-built unit for $87.50 from Emtech or $62.50 as a kit. I would advise purchasing one even if you also have an automatic antenna tuner–makes for a great back-up!

Other options?

This is by no means a comprehensive list of portable ATUs to pair with the IC-705, just a few suggestions. In fact, companies like MFJ Enterprises make a number of manual tuners that could easily be taken to the field and require no power source (much like the ZM-2 above).

Please comment if you have experience with other types of ATUs and please include links if possible!

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Comparing the Icom IC-705 and Icom IC-7300 with the Xiegu GSOC G90 combo

I was recently asked to make a table comparing the basic features and specifications of the new Xiegu GSOC/G90 combo,  and comparing it with the Icom IC-7300 and IC-705.

This is by no means a comprehensive list, and I plan to add to it as I test the GSOC. It doesn’t include some of the digital mode encoding/decoding features yet. I’m currently waiting for the next GSOC firmware upgrade (scheduled for November 20, 2020) before I proceed as it should add mode decoding, audio recording, fix CW mode latency, and add/fix a number of other items/issues.

Comparison table

Click to enlarge

Quick summary of comparison

At the end of the day, these radios are quite different from each other. Here’s a quick list of obvious pros and cons with this comparison in mind:

Xiegu GSOC G90 combo ($975 US)

Pros:

  • The GSOC’s 7″ capacitive touch screen is the biggest of the bunch
  • The GSOC can be paired with the G90 or X5101 transceivers (see cons)
  • The GSOC controller is connected to the transceiver body via a cable, thus giving more options to mount/display in the shack
  • The G90 transceiver (read review) is a good value and solid basic transceiver
  • Upgradability over time (pro) though incomplete at time of posting (con)
  • GSOC can be detached, left at home, and G90 control head replaced on G90 body to keep field kit more simple (see con)

Cons:

  • The GSCO is not stand-alone and must be paired with a Xiegu transceiver like the Xiegu G90 or X5105. The X5105 currently has has limited functionality with the GSOC but I understand this is being addressed. (see pro)
  • I don’t believe the GSOC can act as a sound card interface if directly connected with a computer (I will correct this if I discover otherwise). This means, for digital modes, you may still require an external sound card interface
  • No six meter coverage like the IC-7300 and IC-705
  • Quite a lot of needed cables and connections if operating multiple modes; both GSOC and G90 require separate power connections
  • At time of posting, a number of announced features missing in early units, but this should be addressed with a Nov 20, 2020 firmware upgrade
  • Replacing and removing G90 control head requires replacing four screws to hold in side panels and secure head to transceiver body (see pro)

Icom IC-7300 ($1040 US)

Pros:

  • Built-in sound card interface for for easy digital mode operation
  • Excellent receiver specifications (click here to view via Rob Sherwood’s table)
  • Possibly the most popular transceiver Icom has ever made (thus a massive user base)
  • Well thought-through ergonomics
  • Includes six meter operation and expanded RX frequencies (compared with G90/GSOC); high frequency stability

Cons: 

  • The heaviest of this group (con), but it is a 100 watt transceiver (pro)
  • Smaller display than the GSOC
  • Touch sensitive display (not capacitive like the GSOC)
  • Faceplate not detachable like the G90

Icom IC-705 ($1300 US)

Pros:

  • Built-in sound card interface for for easy digital mode operation
  • Excellent receiver specifications (click here to view via Rob Sherwood’s table)
  • Can use swappable Icom HT battery packs
  • Well thought-through ergonomics, but on that of the IC-7300
  • Includes six meters and VHF/UHF multi-mode operation with high frequency stability
  • Includes D-Star mode
  • Includes wireless LAN, Bluetooth, and built-in GPS
  • Weighs 2.4 lbs/1.1 kg (lightest and most portable of the bunch)

Cons:

  • No internal ATU option
  • Maximum of 10 watts of output power
  • The priciest of this bunch at $1300 US

In short, I’d advise those looking for a 100 watt radio, to grab the Icom IC-7300 without hesitation. It’s a solid choice.

If you’re looking for the most portable of these options, are okay with 10 watts of maximum output power, and don’t mind dropping $1300 on a transceiver, the Icom IC-705 is for you. You might also consider the Elecraft KX3, Elecraft KX2, and lab599 Discovery TX-500 as field-portable radios. None of them, however, sport the IC-705 display, nor do they have native VHF/UHF multimode operation (although there is a limited KX3 2M option). The IC-705 is the only HF QRP radio at present that also has LAN, Bluetooth, and built-in GPS. And, oh yes, even D-star.

If you’re a fan of the Xiegu G90 or already own one, give the GSOC controller some consideration. It offers a more “modular” package than any of the transceivers mentioned above in that the controller and G90 faceplace can be swapped on the G90 body. The GSOC screen is also a pleasure since there are two USB ports that can connect a mouse and keyboard (driver for mine were instantly recognized by the OS).  The GSOC/G90 combo is a bit “awkward” in that a number of cables and connections are needed when configured to operate both SSB and CW: a CW key cable, Microphone cable, I/Q cable, serial control cable, power cable for the GSOC, and a power cable for the G90.  This doesn’t include the cables that might be needed for digital operation. I dislike the fact that the CW cable can only be plugged into the transceiver body instead of the GSOC controller like the microphone. Still: this controller adds functionality to the G90 (including FM mode eventually) that may be worth the investment for some.

Did I miss something?

I’ll update this list with any obvious pros/cons I may have missed–please feel free to comment if you see a glaring omission! Again, these notes are made with a comparison of these three models in mind, not a comprehensive review of each. I hope this might help others make a purchase decision.

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Using the new Xiegu GSOC and G90 transceiver combo for shortwave broadcast listening–?

Listening to Radio Prague via WRMI with the Xiegu GSOC

Many thanks to SWLing Post contributor, Tim R, who writes:

Dear Thomas,

First of all thank you so much for the all of the energy you put into the SWLing Post. When crazy things are happening in the world it’s a very welcome sanctuary! Sending you some coffee money.

I plan to become a ham radio operator next year. Bought the book last week and once I finish a large project for work, I’m on it. Of course, the Tech license will only give me limited exposure to HF, but I’m already plotting an HF radio purchase because I can’t WAIT do do some SWLing with it. Up to this point, I’ve only owned portable radios and never really have used external antennas other than some cheap wire.

My question…

I’ve been considering grabbing a Xiegu G90 because it seems to be a nice comprehensive beginner’s HF rig and is very affordable. I read your review and understand your caveat that there’s no way to completely disengage the transmit so that it can’t be accidently hit if connected to an RX only antenna. I’m not worried about that because I’m going to hang a G5RV wire antenna and use it both for TX and RX. No problem if RF is accidently sent through it.

Of course, there’s a lot of buzz in the Xiegu community about the new GSOC controller. I had not planned to exceed $600 for my radio purchase, but I love the idea of the controller. But when I add $550 for the controller and $450 for the radio, all the sudden I’m at $1,000.

After some deep soul-searching (and let’s be frank here, a blessing from my wife and CFO) I’ve decided to raise my budget to $1,000.

All of this to ask, if you had $1,000, would you buy the G90 and GSOC controller, or would you get something else keeping in mind I want to use this as much for shortwave listening as for future ham radio work?

Any advice would be appreciated.

-Tim

Thanks for your question, Tim! And thanks for giving me a complete picture of your budget/radio requirements and the antenna you plan to use.

I’ll try to answer your question here, but understand this is more what I would do if I were in your shoes. This is a pretty simple question, but not simple to answer because there are so many options on the market.

Xiegu GSOC and G90 combo option

Keeping in mind, I feel like the GSOC is a work in progress at the moment and not fully developed–check out my initial review. Once the next firmware update is available it could certainly solve a number of small issues I found with the unit. It works, but it’s not a refined product yet.

It’s ironic, actually. When I received your message this morning, Tim, I was SWLing with the GSOC and G90–listening to Radio Prague on WRMI. In the end, though, the GSOC is primarily an enhanced interface for the G90. While it does add some extra functionality (and should, over time, add much more) it doesn’t really change the performance characteristics of the G90. I’d check out my G90 review for more info about performance.

Would I purchase the G90/GSOC combo if I were in your shoes? Again, it’s early days, so I don’t feel comfortable making a recommendation call yet. The G90 is, without question, a great value at $450 (often even less) investment. I like it primarily as a field radio, though, and once you add the GSOC to the mix, it’s a little less portable because it’s two units with quite a few interconnect cables. Of course, you can swap the GSOC unit for the G90 control head at any time, but that involves attaching and re-attaching the control head each time (there’s no accessible serial port on the back of the G90, for example)

If you’re a huge fan of the G90, the GSOC should eventually be a worthy addition. At present, for your use as a new ham and for SWLing, I’d perhaps consider other options too.

The Icom IC-7300

The Icom IC-7300 SDR transceiver

Since you’ve raised your budget to $1,000, I’d consider adding the Icom IC-7300 to your list. At present, via Universal Radio you can buy a new IC-7300 for a net price of $1039.95 after rebates. Sometimes, the price will go even lower although during the C-19 pandemic, I think that’s less likely to happen since supplies are lower than normal for many items.

The IC-7300 has better performance specs than the G90 and can output a full 100 watts if you like. The display is touch sensitive rather than capacitive like the GSOC. The display is also much smaller than that of the GSOC. The IC-7300 has a lower noise floor than the G90.

I think the IC-7300 is a great radio for SWLing, but the audio for broadcasts is sort of “flat.” You might check out this post where we did some audio comparisons. It does have native broadcast recording to an SD card, which I love. The GSOC should be adding this soon, too.

I would include the new Icom IC-705 as a recommendation here, too, but it’s $300 over your budget.

A PC-connected SDR and separate transceiver

 

This might be the option I’d take if I were in your shoes.

Get the 20 watt Xiegu G90 ($450) as planned or consider a radio like the 100 watt  Yaesu FT-891 ($640), Both of these radios are general coverage and would serve you well for SWLing and ham radio activities. I’d personally invest the bit extra and get the FT-891 since it would also give you 100 watts output and even has advanced features like memory keying.

We actually mentioned both radios in a similar post this year.

If you buy the pricier Yaesu FT-891, you’d still have $360 to invest in your shack!

I’d then buy an Airspy HF+ Discovery ($170–my review here) or SDRplay RSPdx ($200–my review here) and get all of the benefits of a PC-connected SDR.

These SDRs would take your SWLing to the next level. They have uncompromised performance for the price.

Both companies continuously improve their products/applications based on customer feedback. Indeed, check out some of our recent posts about SDR# free upgrades. Mind blowing stuff–!!!

You could even use the SDR as a panadapter for your transceiver which would give you the ability to have a full-screen spectrum display on an external monitor at home.

More options?

Of course, these answers only scratch the surface. I haven’t even included used, late model gear in these recommendations.

I’d like to give you a firm recommendation about the GSOC and G90 combo, but I’m waiting to see how this next firmware upgrade goes–early days still.

Post readers: Please comment if you have even more options/suggestions for Tim. What works for you within a $1,000 budget.

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Icom IC-R30 new firmware (v 1.11) now available

Many thanks to SWLing Post contributor, Markku Koskinen, who shares the following:

Just letting you know that Icom has released new firmware for the IC-R30 receiver.

Please read carefully and follow all instructions:

https://www.icomjapan.com/support/firmware_driver/

Changes from version 1.10: Fixed the problem of when the ANL of the band that is not used is ON, while the Dualwatch function is OFF, the received DCR audio may not be output from the speaker.

This firmware is for the USA version that has a serial number beginning with “16”.

This firmware is for non-USA versions that have a serial number beginning with other than “16”.

Thank you for the tip, Markku!

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Taking the Icom IC-705 on a shortwave and mediumwave field trip

Many thanks to SWLing Post contributor, 13dka, who shares the following:

Yesterday evening, I took the Icom IC-705 to the dike for the first time (got it on Thursday and spent a lof of time with familiarization).

Since it was already too dark, wet and cold for all the fuss with antennas, I decided to just put a telescopic whip on a tiny magmount on the car roof, curious what the 705 would make out of that. That magmount is the worst thing ever, too much cheap RG-174 seems to attenuate the signal from the whip (possibly some impedance catastrophe), my portables don’t like that thing at all.

So the antenna was as bad as it gets but…it demonstrated what the 705 can do with extremely faint signals! I had really good and quiet reception even when signals were not at all showing up on the S-Meter or much on the waterfall. I had to turn on preamp 2 and crank up the scope “Ref” gain up to see anything, but SNR was great, I didn’t have the feeling that I’m missing many stations and it even worked pretty well on medium wave to longwave, with the signal really tapering off only below 500 kHz and I learned why omnidirectional whips never caught on on MW! ?

AM band scan:

31m band scan:

So yes, as an SWL/BCL receiver it will likely perform as good as it possibly gets with literally any antenna or anything that could stand in for an antenna, the only thing it doesn’t have is sync but since it can tune in 1 Hz steps it can truly zero beat in ECSS, it has notch/autonotch (indispensable also on congested broadcast bands), passband tuning, if I didn’t get that wrong it has 10,000 memories and the 32 GB SD card I was putting in is good for more than 3 weeks of recording 24/7. With some regular BNC whip it’s still a cool bedside radio in a hotel room (no alarm function tho), also good for some VHF/UHF in-house good night 88s between licensed dads and daughters if you plug in the mic, which you don’t have to.

What a cool toy, I’m sure I will still love it when the honeymoon is over!

Thanks for sharing this, and for those band scans. Wow! And I love the “also good for some VHF/UHF in-house good night 88s between licensed dads and daughters”–! Ha ha! That is a real possibility.

Your IC-705 experience on MW and SW is similar to mine. I’ve used the IC-705 a number of times in the field and find that it has a superb and capable general coverage receiver. I’ve also coupled it with my homemade NCPL antenna and have been very pleased with the results. I couldn’t be more pleased.

You’ll find the twin passband filters are incredibly effective at knocking out adjacent signal spill-over. And, yes, the auto notch feature is excellent for killing hets in your audio. I’ve even used the notch manually and like many of my PC-connected SDRs, the filter can be adjusted in width.

I think you’ll continue to enjoy the IC-705 well beyond the honeymoon phase and I’m hoping you might even post some more comparisons at the dike!

AS I mentioned in previous posts, I had fully intended to sell the IC-705 after my review period, but I’ve grown to love this radio so much, that is no longer going to happen.

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Icom IC-705 blind audio tests: Let’s take a look at your choices!

Before I had even taken delivery of the new Icom IC-705 transceiver, a number of SWLing Post readers asked me to do a series of blind audio comparison tests like I’ve done in the past (click here for an example).

Last week, I published a series of five audio tests/surveys and asked for your vote and comments. The survey response far exceeded anything I would have anticipated.

We received a total of 931 survey entries/votes which only highlights how much you enjoy this sort of receiver test.

In this challenge, I didn’t even give you the luxury of knowing the other radios I used in each comparison, so let’s take a look…

The competition

Since the Icom IC-705 is essentially a tabletop SDR, I compared it with a couple dedicated PC-connected SDRs.

WinRadio Excalibur SDR

The WinRadio Excalibur

I consider the WinRadio Excalibur to be a benchmark sub $1000 HF, mediumwave, and longwave SDR.

It is still my staple receiver for making off-air audio and spectrum recordings, and is always hooked up to an antenna and ready to record.

In the tests where I employed the WinRadio Excalibur, I used its proprietary SDR application to directly make recordings. I used none of its advanced filters, AGC control, or synchronous detection.

Click here to read my original 2012 review of the WinRadio Excalibur.

Airspy HF+ SDR

The Airspy HF+ SDR

I also consider the Airspy HF+ SDR to be one of the finest sub-$200 HF SDRs on the market.

The HF+ is a choice SDR for DXing. Mine has not been modified in any way to increase its performance or sensitivity.

In the test where I employed the HF+ I used Airspy’s own SDR application, SDR#, to directly make recordings. I used none of its advanced filters, AGC control, noise reduction, or synchronous detection.

Belka-DSP portable receiver

The Belka-DSP

I recently acquired a Belka-DSP portable after reading 13dka’s superb review.

I thought it might be fun to include it in a comparison although, in truth, it’s hardly fair to compare a $160 receiver with a $1300 SDR transceiver.

The Belka, to me, is like a Lowe HF-150 in a tiny, pocket package.

Elecraft KX3 QRP transceiver

The Elecraft KX3

The KX3 is one of the best transceivers I’ve ever owned. Mine has the CW roofing filter installed (only recently) and is, without a doubt, a benchmark performer.

Click here to read my full review.

If you check out Rob Sherwood’s receiver test data table which is sorted by third-order dynamic range narrow spaced, you’ll see that the KX3 is one of the top performers on the list even when compared with radios many times its price. Due to my recording limitations (see below) the KX3 was the only other transceiver used in this comparison.

Herein lies a HUGE caveat:

The WinRadio application

As I’ve stated in SDR reviews in the past, it is incredibly difficult comparing anything with PC-connected SDRs because they can be configured on such a granular level.

When making a blind audio test with a stand-alone SDR radio like the IC-705–which has less configurability–you’re forced to take one of at least two paths:

  • Tweak the PC-connected SDR until you believe you’ve found the best possible reception audio scenario and use that configuration as a point of comparison, or
  • Attempt to keep the configuration as basic as possible, setting filters widths, AGC to be comparable and turning off all other optional enhancements (like synchronous detection, noise reduction, and advanced audio filtering to name a few).

I chose the latter path in this comparison which essentially undermines our PC-connected SDRs. Although flawed, I chose this approach to keep the comparison as simple as possible.

While the IC-705 has way more filter and audio adjustments than legacy transceivers, it only has a tiny fraction of those available to PC-connected SDRs. Indeed, the HF+ SDR, for example, can actually be used by multiple SDR applications, all with their own DSP and feature sets.

In short: don’t be fooled into thinking this is an apples-to-apples comparison. It is, at best, a decent attempt at giving future IC-705 owners a chance to hear how it compares in real-word live signals.

Recordings

The Zoom H2N connected to my Elecraft KX2.

Another limiting factor is that I only have one stand-alone digital audio recorder: the Zoom H2N. [Although inspired by Matt’s multi-track comparison reviews, I plan to upgrade my gear soon.]

The IC-705 has built-in digital audio recording and this is what I used in each test.

The WinRadio Excalibur and Airspy HF+ also have native audio recording via their PC-based applications.

With only one stand-alone recorder, I wasn’t able to simultaneously compare the IC-705 with more than one other stand-alone receiver/transceiver at a time.

As I mentioned in each test, the audio levels were not consistent and required the listener to adjust their volume control. Since the IC-705, Excalibur, and HF+ all have native recording features, the audio levels were set by their software. I didn’t post-process them.

Blind Audio Survey Results

With all of those caveats and disclaimers out of the way, let’s take a look at the survey results.

Blind audio test #1: 40 meters SSB

In this first test we listened to the IC-705, WinRadio Excalibur, and Belka-DSP tuned to a weak 40 meter station in lower sideband (LSB) mode. Specifically, this was ham radio operator W3JPH activating Shikellamy State Park in Pennsylvania for the Parks On The Air program. I chose this test because it included a weak station calling CQ and both weak and strong stations replying. There are also adjacent signals which (in some recordings) bleed over into the audio.

Radio A: The Belka-DSP

Radio B: The WinRadio Excalibur

Radio C: The Icom IC-705

Survey Results

The Icom IC-705 was the clear choice here.

Based on your comments, those who chose the IC-705 felt that the weak signal audio was more intelligible and that signals “popped out” a bit more. Many noted, however, that the audio sounded “tinny.”

A number of you felt it was a toss-up between The IC-705 and the Belka-DSP. And those who chose the WinRadio Excalibur were adamant that is was the best choice.

The WinRadio audio was popping in the recording, but it was how the application recorded it natively, so I didn’t attempt to change it.

Test #2: 40 meters CW

Icom IC-705In this second test we listened to the Icom IC-705 and the Elecraft KX3 tuned to a 40 meter CW station.

Radio A: Icom IC-705

Radio B: Elecraft KX3

Survey Results

The Elecraft KX3 was preferred by more than half of you.

Based on your comments, those who chose the KX3 felt the audio was clearer and signals had more “punch.” They felt the audio was easier on the ears as well, thus ideal for long contests.

Those who chose the IC-705, though, preferred the narrower sounding audio and felt the KX3 was too bass heavy.

Test #3: Shannon Volmet SSB

In this third test we listened to the Icom IC-705 and WinRadio Excalibur, tuned to Shannon Volmet on 8,957 kHz.

Radio A: WinRadio Excalibur

Radio B: Icom IC-705

Survey

The Icom-705 audio was preferred by a healthy margin. I believe, again, this was influenced by the audio pops heard in the WinRadio recording (based on your comments).

The IC-705 audio was very pleasant and smooth according to respondents and they felt the signal-to-noise ratio was better.

However, a number of comments noted that the female voice in the recording was actually stronger on the WinRadio Excalibur and more intelligible during moments of fading.

Test #4: Voice of Greece 9,420 kHz

In this fourth test we listen to the Icom IC-705, and the WinRadio Excalibur again, tuned to the Voice of Greece on 9,420 kHz.

Radio A: Icom IC-705

Radio B: WinRadio Excalibur

Survey

While the preference was for the IC-705’s audio (Radio A), this test was very interesting because those who chose the Excalibur had quite a strong preference for it, saying that it would be the best for DXing and had a more stable AGC response. In the end, 62.6% of 131 people felt the IC-705’s audio had slightly less background noise.

Test #5: Radio Exterior de España 9,690 kHz

In this fifth test we listened to the Icom IC-705, and AirSpy HF+, tuned to Radio Exterior de España on 9,690 kHz. I picked REE, in this case, because it is a blowtorch station and I could take advantage of the IC-705’s maximum AM filter width of 10 kHz.

Radio A: Icom IC-705

Radio B: Airspy HF+

Survey

The IC-705 was preferred by 79% of you in this test.

Again, very interesting comments, though. Those who preferred the IC-705 felt the audio simply sounded better and had “punch.” Those who preferred B felt it was more sensitive and could hear more nuances in the broadcaster voices.

So what’s the point of these blind audio tests?

Notice I never called any radio a “winner.”

The test here is flawed in that audio levels and EQ aren’t the same, the settings aren’t identical, and even the filters have slightly different shapes and characteristics.

In other words, these aren’t lab conditions.

I felt the most accurate comparison, in terms of performance, was the 40M CW test with the KX3 because both employed similar narrow filters and both, being QRP transceivers, are truly designed to perform well here.

I essentially crippled the WinRadio Excalibur and Airspy HF+ by turning off all all but the most basic filter and AGC settings. If I tweaked both of those SDRs for optimal performance and signal intelligibility, I’m positive they would have been the preferred choices (indeed, I might just do another blind audio test to prove my point here).

With that said, I think we can agree that the IC-705 has brilliant audio characteristics.

I’ve noticed this in the field as well. I’m incredibly pleased with the IC-705’s performance and versatility. I’ll be very interested to see how it soon rates among the other transceivers in Rob Sherwood’s test data.

The IC-705 can actually be tailored much further by adjusting filter shapes/skirts, employing twin passband tuning and even using its noise reduction feature.

If anything, my hope is that these blind audio tests give those who are considering the Icom IC-705 a good idea of how its audio and receiver performs in real-word listening conditions.


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