A couple of months ago, Retevis sent me a pre-production Ailunce HS4 10 meter radio to evaluate and provide feedback on. I've been playing with it for a while, and now that the radio is released, I can publicly review this radio.
Let's get the obvious out of the way: This is a 30 watt CB style radio, sold as a 10 meter radio but it can obviously be converted for use on 11 meters. What you decide to do with your radio is your business, not mine. For the purposes of this review, I've spent a lot of time using it as a 10 meter radio, to see how it performs and also pass along to others how to effectively use a radio like this on 10 meters.
This is an all mode radio, as evidenced by the mode knob on the front. There is an 1/8" CW input on the rear, next to the speaker output and micro-USB, which is used for programming:
The radio is advertised at the following max power output levels: 12 watts CW/AM, 40 watts FM, 35 watts SSB. Using a Bird43P with a 50 watt HF element, I measured 12 watts CW/AM, and 30 watts on all other modes. It has features that serve little use on ham radio such as echo and roger beep, but a slight bit of reverb on SSB or AM can sound good in certain situations. Even the W2IHY EQ Plus has a feature to add reverb if you desire it, so there's no reason to brow beat having echo on a 10 meter radio. The radio is channelized into 6 bands/banks of 60 channels. The channels come from the factory spaced 5 khz apart. The first thing you'll want to do is download the HS4 software from Retevis' website. Setting the various functions from within the radio is easy enough, but given the limited display characters, some menus are a bit cryptic. The manual certainly helps, as well.
Basic Operation
The first setting you'll want to change is the behavior of the CLARIFIER knob. To effectively use this on the ham bands, you'll want the clarifier to change both TX and RX, and you should change the clarifier push setting to adjust the step frequency. Once you've done this, you can use it to adjust the frequency in less than the default 5 khz channels. The procedure I landed on to sweep a large portion of the band looking for activity, is set the mode of interest, like USB. Then I use the large channel knob to start at the bottom end of the interested frequency range; in this example let's use 28.380. I set the clarifier to 1khz increment and turn it left and right quickly to sweep a couple of khz up and down, then change the channel to the next step, 28.385 repeat the procedure. When the band is very active, you don't need to mess with the clarifier to find activity; just using the channel knob gets you close enough and then you can use the clarifier to hone in on the actually frequency the traffic is on. It's a little more tedious than a radio with a real VFO, but it works. Using this method, I've successfully made quite a few contacts. One thing to remember, the clarifier has stops at 7 o'clock and 5 o'clock. When you change the channel using the large channel knob, it doesn't know where the clarifier is at so it's best to reset it back to 12 o'clock before changing the large knob. If you change the frequency using the clarifier, then change the channel a few times, change the clarifier again, when you come back to the prior frequencies, it remembers the frequency you left the channel at, regardless of clarifier position. If you turn the radio off, you can reset to the clarifier to 12 o'clock; the radio will revert to the programmed channels if you get it too out of sorts.
I tested CW using a straight key. When the radio is in RX mode, the first tap of the key causes the radio to start TX, but it cuts off the length of the first dit/dah, which means the TX/RX switch isn't very fast. After that, it's fine, but if found myself doing a quick dit at the beginning of each transmission, which if you do it fast enough, doesn't get transmitted but switches into TX mode. You're not going to do fast CW with this radio, but you can operate.
Using FM Repeaters
You really need the programming software to set up the radio to use FM repeaters. Without the software, the only way to setup a transmit offset is changing the clarifier to adjust the TX frequency. The CTCSS tones and DCS codes are set using a numeric value (1, 2, 3, 4, etc.). The manual I received with the radio was also pre-production and they accidentally left out what the numeric values represented, but a quick email to the company solved that problem. I'm told the manual now includes a table of values. If you want, you can program a bunch of different channels with different tones that equate to the various repeaters you regularly use. Here's an example of how you might do that:
In reality, in North America there are only a few RX frequencies used by FM Repeaters and they all have the same offset. Some people might want to just program in the main RX/TX pairs and then use the menu to change the CTCSS when working a different repeater. If you choose the latter, you'll need to keep the CTCSS lookup table handy. And since there's no way to rename memories on a radio like this, you'll need to make a table of anything you program using the example above. Regardless, it works and I've checked in a few times on a local 10m repeater.
Other Useful Features
The HS4 incorporates digital noise reduction for both transmit and receive. It also has a noise gate you can enable for TX. I use the RX noise reduction routinely on SSB and it really works well. There's button labeled HI CUT on the front that also helps reduce the white noise. As I'm writing this, I'm listening to JE7MGC from Japan making contacts on 28.450 using both the TX noise reduction and HI Cut enabled.
My old 1999 Jeep Wrangler has quite a bit of ignition noise, despite all my efforts over the years to get rid of it. But this is why HF radios come with a noise blanker. I temporarily wired up the HS4 in the Jeep to test the HS4 NB and it worked great.
The included microphone is an electret mic with up/down buttons and another button that operates the auto squelch function. A nice feature of this radio is a setting that allows you to switch the mic setting for use with a dynamic mic. The manual does not include the mic wiring pinout, so I asked for it and have included it:
The HS4 also has high SWR protection, killing the TX when the SWR value exceeds the setting you program. The default is 10:1 SWR, but you can set it as low as 1.2:1 or as high as 20:1. It also includes voltage protection: if the supplied power is outside of the expected 10.5-16 volts, it won't allow you to transmit if this feature is enabled. The rig also has the ability to scan channels. When you program the frequencies, you can tell it whether or not you want it included in the scan list.
IMD Test
Retevis asked me if I have the ability to perform an IMD test. While I don't have a "lab grade" test setup, I do have the ability to do a rudimentary test. I have an Aursinc TinySA Ultra that is capable of doing some basic SSB IMD testing. (Note, the original TinySA cannot do this). I put a homebrew RF sampler inline into a dummy load and set the RF Power at about 1/2, ran into a 40 db attenuator into the TinySA Ultra. To generate the necessary 700Hz and 1900Hz tones, I used an Android app called "Frequency Generator", which also lets you set the volume balance of the two frequencies. I simply coupled the phone speaker to the mic and took a reading. In the results, you can tell that I didn't get the balance set perfectly, but it's still good enough to get a reading:
The HS4 is advertised as -25db or better 3rd order IMD and -35db or better 5th order. This plot shows that 3rd order is exactly -25db and 5th order is about -32db (I forgot to put the markers on the graph). So, I would say it performs as advertised. More expensive HF rigs will perform better than this (and they should) but at this price point, you're getting the same performance that is considered acceptable in a CB radio.
Issues
As I already mentioned, my radio is a pre-production model. The biggest issue that I've reported is that sometimes turning the channel and clarifier results in erratic frequency/channel changes. When you change the channel slowly, sometimes it doesn't change or sometimes it skips a channel. When you do a quicker, more solid change, it works fine. I believe they just need a little higher quality encoder.
Summary
Let's remember that this is a sub $200 radio. As of this writing, you can get one on sale for $177 on Amazon. For $20 more, you can get an included 45" center coil-loaded 2 piece mag mount antenna. The mag mount antenna is very similar to the one Radio Shack used to sell the CB days. The transmit audio quality is very clear and articulate; it's a nice sounding radio even with the stock mic. The digital noise reduction works quite well; if you've never owned a rig with it built in, you owe it to yourself to try it out. If you have your tech license or equivalent and want something inexpensive to work 10 meters CW and SSB, this will definitely get you on the air making contacts. 30 watts power output is more than enough with a decent antenna and good conditions. The fact that programming software is included makes it more versatile that you would expect - it's very easy to store multiple frequency plans and load them on the fly, with a simple radio reboot to execute. And, if you really want to use it on 11m and understand the legalities, there's an option for that, too.
Let's get the obvious out of the way: This is a 30 watt CB style radio, sold as a 10 meter radio but it can obviously be converted for use on 11 meters. What you decide to do with your radio is your business, not mine. For the purposes of this review, I've spent a lot of time using it as a 10 meter radio, to see how it performs and also pass along to others how to effectively use a radio like this on 10 meters.
This is an all mode radio, as evidenced by the mode knob on the front. There is an 1/8" CW input on the rear, next to the speaker output and micro-USB, which is used for programming:
The radio is advertised at the following max power output levels: 12 watts CW/AM, 40 watts FM, 35 watts SSB. Using a Bird43P with a 50 watt HF element, I measured 12 watts CW/AM, and 30 watts on all other modes. It has features that serve little use on ham radio such as echo and roger beep, but a slight bit of reverb on SSB or AM can sound good in certain situations. Even the W2IHY EQ Plus has a feature to add reverb if you desire it, so there's no reason to brow beat having echo on a 10 meter radio. The radio is channelized into 6 bands/banks of 60 channels. The channels come from the factory spaced 5 khz apart. The first thing you'll want to do is download the HS4 software from Retevis' website. Setting the various functions from within the radio is easy enough, but given the limited display characters, some menus are a bit cryptic. The manual certainly helps, as well.
Basic Operation
The first setting you'll want to change is the behavior of the CLARIFIER knob. To effectively use this on the ham bands, you'll want the clarifier to change both TX and RX, and you should change the clarifier push setting to adjust the step frequency. Once you've done this, you can use it to adjust the frequency in less than the default 5 khz channels. The procedure I landed on to sweep a large portion of the band looking for activity, is set the mode of interest, like USB. Then I use the large channel knob to start at the bottom end of the interested frequency range; in this example let's use 28.380. I set the clarifier to 1khz increment and turn it left and right quickly to sweep a couple of khz up and down, then change the channel to the next step, 28.385 repeat the procedure. When the band is very active, you don't need to mess with the clarifier to find activity; just using the channel knob gets you close enough and then you can use the clarifier to hone in on the actually frequency the traffic is on. It's a little more tedious than a radio with a real VFO, but it works. Using this method, I've successfully made quite a few contacts. One thing to remember, the clarifier has stops at 7 o'clock and 5 o'clock. When you change the channel using the large channel knob, it doesn't know where the clarifier is at so it's best to reset it back to 12 o'clock before changing the large knob. If you change the frequency using the clarifier, then change the channel a few times, change the clarifier again, when you come back to the prior frequencies, it remembers the frequency you left the channel at, regardless of clarifier position. If you turn the radio off, you can reset to the clarifier to 12 o'clock; the radio will revert to the programmed channels if you get it too out of sorts.
I tested CW using a straight key. When the radio is in RX mode, the first tap of the key causes the radio to start TX, but it cuts off the length of the first dit/dah, which means the TX/RX switch isn't very fast. After that, it's fine, but if found myself doing a quick dit at the beginning of each transmission, which if you do it fast enough, doesn't get transmitted but switches into TX mode. You're not going to do fast CW with this radio, but you can operate.
Using FM Repeaters
You really need the programming software to set up the radio to use FM repeaters. Without the software, the only way to setup a transmit offset is changing the clarifier to adjust the TX frequency. The CTCSS tones and DCS codes are set using a numeric value (1, 2, 3, 4, etc.). The manual I received with the radio was also pre-production and they accidentally left out what the numeric values represented, but a quick email to the company solved that problem. I'm told the manual now includes a table of values. If you want, you can program a bunch of different channels with different tones that equate to the various repeaters you regularly use. Here's an example of how you might do that:
In reality, in North America there are only a few RX frequencies used by FM Repeaters and they all have the same offset. Some people might want to just program in the main RX/TX pairs and then use the menu to change the CTCSS when working a different repeater. If you choose the latter, you'll need to keep the CTCSS lookup table handy. And since there's no way to rename memories on a radio like this, you'll need to make a table of anything you program using the example above. Regardless, it works and I've checked in a few times on a local 10m repeater.
Other Useful Features
The HS4 incorporates digital noise reduction for both transmit and receive. It also has a noise gate you can enable for TX. I use the RX noise reduction routinely on SSB and it really works well. There's button labeled HI CUT on the front that also helps reduce the white noise. As I'm writing this, I'm listening to JE7MGC from Japan making contacts on 28.450 using both the TX noise reduction and HI Cut enabled.
My old 1999 Jeep Wrangler has quite a bit of ignition noise, despite all my efforts over the years to get rid of it. But this is why HF radios come with a noise blanker. I temporarily wired up the HS4 in the Jeep to test the HS4 NB and it worked great.
The included microphone is an electret mic with up/down buttons and another button that operates the auto squelch function. A nice feature of this radio is a setting that allows you to switch the mic setting for use with a dynamic mic. The manual does not include the mic wiring pinout, so I asked for it and have included it:
The HS4 also has high SWR protection, killing the TX when the SWR value exceeds the setting you program. The default is 10:1 SWR, but you can set it as low as 1.2:1 or as high as 20:1. It also includes voltage protection: if the supplied power is outside of the expected 10.5-16 volts, it won't allow you to transmit if this feature is enabled. The rig also has the ability to scan channels. When you program the frequencies, you can tell it whether or not you want it included in the scan list.
IMD Test
Retevis asked me if I have the ability to perform an IMD test. While I don't have a "lab grade" test setup, I do have the ability to do a rudimentary test. I have an Aursinc TinySA Ultra that is capable of doing some basic SSB IMD testing. (Note, the original TinySA cannot do this). I put a homebrew RF sampler inline into a dummy load and set the RF Power at about 1/2, ran into a 40 db attenuator into the TinySA Ultra. To generate the necessary 700Hz and 1900Hz tones, I used an Android app called "Frequency Generator", which also lets you set the volume balance of the two frequencies. I simply coupled the phone speaker to the mic and took a reading. In the results, you can tell that I didn't get the balance set perfectly, but it's still good enough to get a reading:
The HS4 is advertised as -25db or better 3rd order IMD and -35db or better 5th order. This plot shows that 3rd order is exactly -25db and 5th order is about -32db (I forgot to put the markers on the graph). So, I would say it performs as advertised. More expensive HF rigs will perform better than this (and they should) but at this price point, you're getting the same performance that is considered acceptable in a CB radio.
Issues
As I already mentioned, my radio is a pre-production model. The biggest issue that I've reported is that sometimes turning the channel and clarifier results in erratic frequency/channel changes. When you change the channel slowly, sometimes it doesn't change or sometimes it skips a channel. When you do a quicker, more solid change, it works fine. I believe they just need a little higher quality encoder.
Summary
Let's remember that this is a sub $200 radio. As of this writing, you can get one on sale for $177 on Amazon. For $20 more, you can get an included 45" center coil-loaded 2 piece mag mount antenna. The mag mount antenna is very similar to the one Radio Shack used to sell the CB days. The transmit audio quality is very clear and articulate; it's a nice sounding radio even with the stock mic. The digital noise reduction works quite well; if you've never owned a rig with it built in, you owe it to yourself to try it out. If you have your tech license or equivalent and want something inexpensive to work 10 meters CW and SSB, this will definitely get you on the air making contacts. 30 watts power output is more than enough with a decent antenna and good conditions. The fact that programming software is included makes it more versatile that you would expect - it's very easy to store multiple frequency plans and load them on the fly, with a simple radio reboot to execute. And, if you really want to use it on 11m and understand the legalities, there's an option for that, too.
