CHOYONG LC100 FIRST LOOK

MULTI-BAND, SMART INTERNET RADIO!  

The LC100 is the latest offering from Chinese radio designer, Choyong. According to their company profile, their aim is to become the world's best radio brand, and judging by their achievements so far, they seem to be heading in the right direction!

Having previously purchased their LC90, I have been eagerly awaiting the next generation of smart radios. The LC90 has been a joy to use, but I must admit, over time, some very  minor irritations started to annoy. 

When the whispers of a new model started circulated, I was very excited and monitored the Choyong website and social media portals on an almost daily basis! And so (at last) - the LC100 has finally arrived. I ordered mine directly from the manufacturer and paid for express delivery, which took about a week to reach the UK.

Now let's just address the issues of trust which so many people have when it comes to buying directly from China. Personally, I have never had any problems whatsoever and I've bought many items directly from Chinese manufacturers including the wonderful FX-CR4. Sure, I'd prefer to visit a local store and buy from there, but that's just not possible right now, so I buy direct and enjoy being a part of the growth of a new manufacturer who is working hard to create the products which enthusiasts like me want.

And let me tell you - Choyong usually listen to their customer base and they respond quickly to complaints, queries and wish-lists. Where possible, regular firmware updates ensure that the users get the changes they want. 

Okay, so on with the radio. First and foremost, the LC100 is an SDR multi-band, multi-mode radio with AM, FM, MW, SW, SSB (and DAB if you pay extra when ordering - it wasn't available when I ordered). 

Frequency Ranges...

• LW - 153-279KHz
• MW - 520-1,710KHz
• SW - 2300-29,999KHz
• FM - 64-108MHz

There is no AirBand coverage. I was really hoping that the LC100 would add this to their new model, but sadly not. I'm guessing many people will be disappointed with this omission, although not everyone.

There's another disappointment too - no flip-stand! Again, I was really hoping Choyong would have added that feature to their flagship radio. Looks like I'll have to add my own again. You can see the one I opted for in the image below. They come as a pair and have two different angle settings. I believe Choyong are using the excuse that fitting a flip-stand would have compromised the fidelity of the speaker, but that's just nonsense. Tecsun (and others) manage to do it very easily and effectively.

The radio itself looks lovely in silver or black, but I chose the latter. The case is perfectly sculpted and those rotary dials on either side look big and bold. All the buttons have crystal clear markings and everything is easy to read - even for an old duffer like me!

There's also a much bigger screen in the LC100, which looks to be the same size as my Icom IC705 - that's a fabulous improvement! Other benefits include WiFi 6 with the option to use either 2.4 or 5GHz connections, better internal shielding, improved AI functions and the addition of Bass and Treble adjustment.

For comparison purposes, I decided to pit the LC100 against the Tecsun PL-990X - my best performing portable radio which has similar frequency coverage and costs about the same. I realise that the LC100 is a software defined radio (SDR) and the PL990X is a triple-conversion superhet, but I imagine that many an enthusiast will find them both on their shortlist.

If there wasn’t a Tecsun PL-990X sat next to the LC100, I probably wouldn’t have noticed that the Choyong build quality wasn’t perfect. For some very weird reason, the badge isn’t straight! Exactly the same issue on my LC90. So odd!

Then there’s the aluminium, black anodised dials on either side of the radio - they don’t “feel” as nice as the Tecsun's. This is only noticeable when the two radios are side by side, and it’s a subjective complaint. But there is also a functional difference - the Tecsun dials have a thin layer of material (silicon?) on the front face which makes turning the dials so much more easy! 

The trouble with the LC100 dials is that they're deeply recessed which means that the only practical way of tuning (especially fast-tuning) is to use your thumb on the edge of the dial. To me, that is inviting future problems due to the repeated lateral force applied. Not happy with that at all.

Internally, Choyong have added the high-end TEF6686 chip to the radio to boost the overall receiver performance, in addition to the SI4735 used in the LC90, so there are real benefits to choosing the 100 over its predecessor. 

Is it worth upgrading your LC90? As with most other things in life, you have to decide for yourself whether the differences are big enough for you personally! I think most existing LC90 owners will remain happy with their radio and will probably not upgrade straight away - certainly not after reading this review! Sorry Choyong 😬.

I spent quite a few hours doing side-by-side comparisons of the two radios on various frequencies/bands using both the built-in antennas and an external Off-Center-Fed-Dipole with a Z-Match ATU. When connected an external antenna to the LC100, be sure to use a lightweight patch-lead (above) to avoid stressing the 3.5mm socket. 

Thankfully, Choyong have moved the antenna port (along with the other inputs) over to the lefthand edge of the radio, making it far easier to access them compared to the LC90.

Being the newest radio, I was hoping the LC100 would be head and shoulders above the PL-990X, but to be fair, that would have been a very big ask!

Much of the radio comparisons were carried out at a nearby location called Bodie Hill in Glasson, which overlooks Morecambe Bay. It's a fantastic take-off for radio and a beautiful place to spend time - you also get some spectacular sunsets too!

At the time of comparison, the bands weren't great, but that can be helpful, making it easier to see how well radios perform in poor conditions. When the bands are fully open, it's too easy to heap praise on virtually any radio.

Tuning into weak signals showed equal levels of sensitivity between the 100 and the 990 but there was a major issue when tuning in SSB mode. There was a terrible (for want of a better word) chuffing as you changed frequency using the main tuning dial (see an example of this in the video I recorded when back home)…..

SOFT MUTING ISSUE

It’s absolutely awful!  This annoying soft-muting needs sorting out quickly or it could have a dramatic impact on sales! 

I noticed another problem while I was recording the first video! This was relating to the screen interfering with the signal. I was tuned into RAF Volmet 5.450 and could hear no signal until the screen went to sleep and then the signal could be heard. This was indoors, using the telescopic whip….

SCREEN INTERFERENCE

Since I've started uploading videos here, I might as well continue and show you another couple. The first one relates to the fact that the RECORD FUNCTION doesn't seem to work correctly. Sure, it records and saves the file to the SDCARD, but when you play back the file, there is no audio. 

Just to be sure that the LC100 had created a silent wav file, I inserted the card into my laptop and it was the same there too, so it's not just a playback issue on the radio. Oh dear!

SILENT RECORDINGS

UPDATE!!! Just as I was about to post this page to my Blog, I tried to record a podcast that I had running in the background and it worked! So maybe the record function is just available for recording internet stuff. After the podcast file worked, I tried recording a BBC Radio 1 stream and that worked too! To be honest, because of copyright laws, I was half expecting it not to, but it did.

Okay so that's better than originally thought, but surely, Choyong could change the firmware so that the record function prevents its use when the operator is trying to use it outside the radio's operating paramaters? And maybe pop up a message to explain why it's not available.

And now for some good news! The telescopic antenna does actually extend from the body, despite rumours to the contrary. 

EXTENDING ANTENNA

Despite poor propagation during testing, I was able to listen to ham radio operators (using the OCFD on a 12M pole), as far away as Eastern Russia and Brazil, which was very pleasing. The LC100 didn’t overload when connected to the OCFD, which was good news considering that there isn't any sort of attenuator switch (as there is on the Tecsun). 

The audio from the large 10W internal speaker is lush and loud! I'd say the Choyong has the edge on the Tecsun here, although this is a subjective call and others may disagree. The speaker design is a 3-driver affair and is very effective - especially with FM broadcast stations, where you tend to use higher volume levels. Bass in particular seemed better controlled on the LC100 than on the PL990X (not to mention the LC90).

I’d be very happy with the performance of the receiver on all bands if Choyong can sort out the issues raised in my videos - having said that, I won’t be selling my Tecsun any time soon.

When radio conditions are very poor (due to propagation or location), the Choyong has a MASSIVE ADVANTAGE over the Tecsun, because you can easily switch to listening to the amazing SMART features of the LC100 and this is where the radio really shines! 

You have access to over 50,000 radio stations across the world! Plus you have access to countless Podcasts and News channels.

Thanks to the excellent ergonomics of the LC100, accessing stations is easy - the menu system is very intuitive. And the icing on the cake is the ability to use the built-in Ai function to access stations, podcasts, news and music via ChatGPT! In the image above, I simply asked for “BBC” and was quickly presented with a list of BBC stations across the world. Excellent!

I can (and do) spend hours and hours exploring this vast world of internet radio stations, enjoying the myriad music genres and content from across the globe. Thanks to the new WiFi-6, connection to the internet is super fast and I've experienced no buffering throughout my listening sessions (unlike my experiences using the LC90). My router is placed centrally in my home and I've had solid, reliable connections indoors and outdoors around the garden.

I also connected the radio to my iPhone's HotSpot and the internet streaming was faultless!

If I wish to listen to some of my favourite music tracks, I simply switch to the files stored on an SDCARD which can be inserted (and left) in the LC100. Access to these files from the screen is also super simple! I should point out that the Tecsun has an SDCARD slot too, but access to the files is very basic indeed. The Choyong displays the music files perfectly and makes it a pleasure to use. I’m very happy with this aspect of the radio.

So in summary, the Choyong LC100 is a great performer on FM and SW apart from that 'AGC chuffing'. I can't even begin to describe how disappointing and annoying this is. I just hope it's firmware-fixable!

The screen interference on certain frequencies is also a huge concern and sadly, that cannot be fixed with firmware updates (as far as I'm aware anyway).

The 'limited' recording problem is not a massive issue to me, but it will be for some people. I know many people love to record their SWL sessions and may buy this radio because it is advertised with a built-in recorder.

So, onto the smart aspects of the LC100. It's fantastic!! I will keep the radio just for that alone! It extends my listening hobby massively and I couldn't really be happier with it. A few minutes ago, I pressed the Ai1 button and said "Amater Radio" and it filled the screen with a long list of amateur radio podcasts. Fantastic!!

Finally, I need to comment on the fact that the radio does not come with a carry-case. That's a shame because the Tecsun did - and it was a very attractive one too. When you're paying top dollar for a flagship product, these details count.

I will come back to this page in a week or so to report any other discoveries - good or bad. Please add your thoughts/findings in the comments section for the benefit of others.

Please bear in mind, that I may have a dodgy sample and if that's the case, I'd be more than happy to rewrite my review. I only ever post truthful facts. No BS!

Thank you for visiting - it's appreciated.

Tom McQuiggan - M7MCQ

 

CHOYONG WEBSITE HERE for overview and specs

 

 

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MY NEXT NEW RADIO!

Regular visitors to this blog will be more than aware that most of my radio activity is QRP based and outdoors - I spend very little time in the shack - almost none during hot weather ☀️! When I do play radio indoors, it’s usually on the wonderful Hermes Lite 2 or the fabulous Elad FDM Duo. I’m over the moon with both radios ❤️❤️

So why then, am I considering a new radio? Is it to replace one of the aforementioned rigs? Or is it to replace my IC-705, G90, FX-4CR or my QMX PLUS?  None of the above! I’m actually committing to buying an additional radio - the new ICOM X-026 which (by all accounts) is the modern replacement for the ubiquitous IC-7100.

Needless to say, there’s a world of speculation about what the X-026 will look like and what it will provide. We’ll find out a whole lot more at the end of August when Icom (hopefully) reveal further details at the Tokyo Ham Fair.

I think they’re going to feature a pop-off front display, but I’d much prefer them to keep it more like the original 7100 with the chunky (and quirky) desktop unit. That thing was so darned versatile, but I do appreciate that a lot of people weren’t as enamoured as I was. Many people buy this type of radio for mobile use and they struggle to mount that head in their car/truck.

I guess we’ll soon find out. As for features, I’m guessing it will be 100W on HF and 50 elsewhere. Hopefully it will include the 4M band for the UK and will have much extended RX capability, including the Airband. I don’t expect it to have an inbuilt ATU though.

Needless to say, it will have DSTAR, WiFi, Bluetooth and GPS as standard (unlike Yaesu’s recent lack-lustre offering) 🙄. I'm REALLY HOPING that they'll introduce something unique and innovative in a radio at this level - maybe something like a network connected head-unit like on the 7760 - a big ask, I know!

I will update this page as I find out more (eg real) information. Excited!!

Tom, M7MCQ

PURE SIGNAL - HERMES LITE 2

HOW DO I  BECOME PURE?

People email me saying they've read my blog-posts about the wonderful Hermes Lite 2 but point out that I don't provide instructions on how to use Pure Signal, so let's fix that right now!  It's a very simple process and can be achieved quickly. Using PS is detailed in the manual, but it seems some people don’t read them, lol. Bear in mind though, I'm a simple M7 license holder, so everything written below is based purely on experimentations. 

There's actually a couple of ways of doing it - internally or externally. I have only used the HL2's internal method, but that might change as I go along.  Anyway, let's start with the easiest way first of all. Anyone can use this method and there's no extra parts to pay for it you already have a Pure Signal output.

Pure Signal (an advanced, adaptive predistortion technique) is used to significantly clean up your transmitted signals by reducing distortion, IMD (Intermodulation Distortion), and harmonics. By sampling a portion of the output and correcting for nonlinearities, it improves transmission quality, reduces splatter and enhances efficiency.

In order for Pure Signal to function on your Hermes Lite, you must start by switching on PS-A (which is the Pure Signal Auto calibration) and DUPLEX (meaning that the radio receives even when transmitting). This is so that the transmitted signal can be monitored, measured and subsequently adjusted. So go to your Thetis software and switch it on (by the way, I'm using V2.10.3.12)...

Then you need to switch on AGC AUTO by double-clicking the text above the AGC until it switches from S-ATT  to  A-ATT. If you forget to do this, Pure Signal will not work properly.

Then go to the menus at the top of the screen and click on LINEARITY. A screen will appear - make sure you have all these settings...

Now find a clear spot on your preferred band and transmit. You will notice that the green   Feedback/Pure Signal 2  markers will change to indicate that your transmission is being examined, measured and adjusted...

That's it! You have PURE SIGNAL! 

 

WHAT ABOUT CONNECTING AN AMP?

So when you use the internal method, everything leaving your HL2 antenna port will be pure as the driven snow. But what if your pure signal goes out to an amplifier? That amplifier could undo all your good work!

Up to now, I've not seen a single post on the internet about this. There's little bits here and a few hints there, but no simple, straightforward guide on how to use Pure Signal with a HL2 and an Amp. So let's hope this post fixes that situation.

In this case, you want to monitor the signal leaving the amp instead of the radio. To do that you need a special splitter which is actually an RF SAMPLER. There are a few samplers available on the market and in the example below, I've shown an Australian sampler from VK3AMP in the illustration...

You will note from my diagram that the Pure Signal connector on the radio is actually an INPUT and not an output as some mistakenly believe. It's very important that the RF Sampler output to this connector is -50dB or greater to avoid overload. Ideally, you should connect the sampler directly to the amplifier's output connector. In the above case, it would mean using an PL239-PL239 Male pass-thru. 

😂 A pretty diagram versus reality 😂

If you are going to insert an ATU in the circuit, it's going to be between the RF Sampler and the Antenna. You should (in this example) put the amplifier into BYPASS mode during tuning.

Note that I have included an RF Choke in the mix too - that's only because I often use a ground mounted vertical which generates problematic common mode currents. If you have no need for one (or for an ATU) then ignore. In this case, the layout would be simpler still...

So there you have it! Pretty straightforward huh? But what if you don't yet have a Pure Signal connector on the rear panel of your transceiver? Don't worry, it's a very simple and cheap mod - all you have to do is buy an RG-178 pigtail from Amazon (other stores are available lol) and solder one end to the connector block which connects the HL2 PCB and the Filter Board.

Note that the center-conductor goes to pin-6 and the shield (twist it all together) goes to both pins 3 and 4.

HL2 Internals

Close-Up

I hope this post proved to be useful to you.

73, Tom, M7MCQ.

 

UPDATE : 24 FEB 2026

Found a competitively priced RF SAMPLER here in the UK - just ordered one for £44. It gets good reviews, so happy days. Also ordered a couple of inline SMA-SMA attenuators in case I need more attenuation than the sampler provides.

The sampler arrived very promptly from the supplier, well packaged and the whole thing looked to be constructed to a very high standard. Excellent value for money!!

If you wish to purchase the VK3AMP sampler, click here. ($150) 😵

 

If you are from the STATES, perhaps this sampler would be a better option....

And here’s another option…

https://www.60dbm.com/product/55db-100w-1-55mhz-rf-sampler-for-pure-signal

73, Tom, M7MCQ.

Q: Explain Pure Signal on the Hermes Lite 2 HL2 + Plus

Q: How do I use Pure Signal on my Hermes Lite 2?

Q: How do I use Pure Signal on my Hermes Lite 2 with an AMPlifier?

Q: How do I connect my amplifier to Pure Signal on the Hermes Lite 2 HL2 Plus?

Micro PA100 100W HF Amp

I recently I came across an amp at a radio rally and it was for sale at just £50 “SOLD FOR PARTS”.  I got my phone out and Googled the device to learn more about it and discovered that they cost £200 new, so I decided to take a chance on it, figuring I could make a quick buck by selling it on Ebay after reviewing it. Sadly, when I got it home, it didn’t work. Dead as a Dodo!  I was gutted, but figured I’d open it up to see if it was a melted mess inside. 

The PCB and all its components looked to be absolutely as new and in perfect condition - just couldn’t figure it out. After spending time staring at the PCB, I noticed that there was an unusual fuse holder. I removed the fuse, tested it and found that it was blown. Needless to say, I didn't have any of these tiny fuses in my box of bits, so I ordered some on eBay and waited for them to arrive (from China).

When I replaced the tiny fuse, I powered the amp up again, using a current-limiting power supply, half expecting it to blow again. But it didn’t! 

With everything apparently working as it should, I connected it to my IC-705 and a Dummy Load. Dropping the 705’s power to 500mW, I got 20W output from the PA100 into a dummy load. A big smile appeared on my face 😄. I started to increase the power and with a full 5W in, it showed 110W out.

The next step was to connect it to its “natural partner”, the Hermes Lite 2. As mentioned in a previous post, I wanted to take advantage of the ability to run the amplifier output through the Hermes’ Pure Signal processor by adding an RF Sampler. 

With the Hermes putting out 750mW the amp was outputting around 25W - perfect (for me).

I went on the 40M band and broke into a QSO between two English operators with booming signals. I was eager to get a good report from them. Sadly, this didn’t quite go to plan 🙄. When I keyed up, I could see distortion on the panadapter and one of the operators told me my audio was indeed badly distorted.

Without any idea what was causing the distortion, I removed the RF Sampler and tried again. This time, the outgoing signal looked perfect and so I recontacted the operator I’d spoken with moments ago. He confirmed that everything sounded fantastic. He told me that there were some Linearity settings in Thetis which would probably resolve the issue.

Sitting there, I wondered if it was simply a case of there not being enough attenuation in the sampler’s coupling output (-50dB), therefore overloading the HL2’s Pure Signal input 🤔. I’d need to add some inline attenuators and experiment more. But that’s for another day - I don’t want to detract from the performance of the amplifier.

The Micro PA100 is a very compact device, with a 100W (or more) output on the 80-6M bands. It has automatic band sensing or you can provide your own interface lead to let your radio force band changes. There is information in the manual to help you achieve this.

I didn’t have an interface lead and since I’m going to be selling this amp, I can’t see the point in making one, so I used the band-sensing and it worked amazingly well - faultlessly even!

The amp also has RF-Sensing which means that you don’t need to fit a PTT SEND line - just transmit and the amp instantly detects the RF. It works well, but I’d still recommend fitting a lead between the two devices. The menu has options for Icom, Yaesu and Xiegu protocols.

Unlike say a Xiegu XPA125, the PA100 doesn’t have an ATU so I connected an LDG Z-100Plus. Now this would present a problem in that initiating a tune could mean the amp could potentially see huge amounts of reflected power and very high swr during the tune-cycle (it will protect itself if it sees anything greater than 2:1).  Thankfully, the PA100 has a BYPASS mode which is accessed by a simple press of the Function button. Once the ATU has found a match, it’s just a case of pressing the Function button again. 

There’s an impressive amount of protection built into the amp which keeps an eye on high swr, and high temperature - there are two fans fitted in a push-pull arrangement. The fans are quick to switch on and although they aren’t noisy, you are certainly aware of their presence. 

There’s also that tiny 20A fuse which protects from over current and even from applying the power supply the wrong way around (I am so pleased that the previous owner wasn’t aware of the existence of the fuse) 😂🤣😂.

The front panel sports just two things a screen and a button! The display is pretty small but extremely clear and easy to read, providing all the information you need. The (function) button switches between PA ON and PA OFF (bypass) and also gives access to other functions. It’s a little odd, but you soon get used to it. The only thing that concerns me about it is that it sometimes doesn’t detect a press which can be annoying. It also makes me question the longevity of the button.

Other than that button though, I must admit that the construction of this cheap Chinese amp is absolutely excellent!! The pcb seems to be a high quality item and the components look to be very well soldered and carefully placed. There’s not even a hint of “cheap tat” that you often get with these budget devices. Everything looks top notch. It’s also a ‘clean’ amp with a measured -60dBc separation between the wanted signal and any unwanted harmonics.

Note the huge heatsink

CONCLUSION

Putting aside the fact that I got this amplifier for a ridiculously low price, I have to say that the Micro PA100 is a great little amp, brimming with features, versatility and safety. It’s good to know too, that the designer is constantly updating the firmware in order to improve the product.

If I needed a 100W amp, then I wouldn’t hesitate to invest in one of these. They can be used with virtually any transceiver, without the need for an interface lead and you’d have to be an idiot to do it any harm (sorry previous owner).

Its compact dimensions and light weight mean it can easily be taken on POTA outings. It’s just a great little all-rounder. For a Foundation License holder, I like the fact that you can transmit under a Watt and get a solid 25 Watts, giving both radio and amp an easy life.

Before I sell it, I’m going to resolve the RF Sampler issue, just because I want to understand what the cause is.

UPDATE : March 11

I ordered some inline attenuators from AliExpress and in view of the severe distortion that I experienced when first trying out the RF Sampler, I connected 30dB attentuation and BINGO it worked a treat!

The amplified signal from the Micro PA100 was now being processed by the HL2’s Pure Signal circuitry and corrected, resulting in a beautifully clean signal. I had many QSO’s all over the world and received complimentary audio reports.

Again, a HUGE round of applause 👏 to the Hermes Lite 2+ for its outstanding value for money. And more applause 👏 to MI0BOT’s version of Thetis and more again 👏 for the wonderfully cheap Micro PA100!

Amp for sale (with sampler) £200!

Thanks for visiting the blog!

73, Tom, M7MCQ.

Manual

AERIAL-51 MODEL 404-UL

There’s no such thing as a perfect lightweight multiband antenna for outdoor use. I’ve tried lots of them over the last few years and the one which has brought me the most success is the SOTABEAMS 20/40 Bandhopper II Linked Dipole. But that covers just two bands.

I have another Sotabeams antenna called the BandSpringer Mini - an End-Fed which covers 7 bands, but for some reason it’s not been a raging success for me, so I seem to be on this never ending search for the holy grail.

Anyway, I decided to try something different - something which I’ve never tried before - an Off Centre Fed Dipole in the form of the MODEL 404UL from Aerial-51.

This Kevlar-strengthened antenna can handle up to 200W and yet it’s extremely light and compact, weighing just 400g including 40ft of coax! Having something which can handle so much power gives you a satisfying reassurance that your FT8 transmissions are not going to overheat the Balun even at 25W. 

The antenna is just as simple to erect as the Bandhopper and although they recommend using something taller, I used my 7M Mast to great effect. You can see in the photo below how it looks. The 40ft coax allows you a great degree of flexibility in choosing where to operate from (a heated garage in this test-case, lol).

TYPICAL SWR READINGS

 

You can see that the profile of my Inverted-V is quite shallow compared to the 404UL diagram, but nevertheless, it really pulled in the signals. 

 

QUICK SAMPLE OF THE 404/705

 

I’m keeping the antenna in this “test location” for another week and will update this page after that. I bought the 404 as a secondhand item and so luckily got it at a bargain price. The value for money was further enhanced by the WindCamp case it came in, plus a pair of mini-reels for winding in the elements (with their string supports) for quick storage and deployment.

After a while, I dumped the reels in favour of normal winders from SotaBeams.

73, Tom, M7MCQ.