RECENT RS-918SSB HF SDR HAM Transceiver

>>>Update (2018, December 4th) - In response to a question about the RS-918, I wrote an answer too long to post, so will add it to the top of this review as an update to my original review: My rating of 4 stars is unchanged, but this "update" may give a flavor of what the RS-918 really is, both good and bad:Q: How do I know that I'll receive the latest Revision?A: You have to trust that the current shipping version of the hardware is "OK". For well over a year, it has been for most people, but as a made in China product, and one "pirated" from a kit developed by others in the West (M0NKA's mcHF), the quality can be "dodgy". E.g., mine worked, but had a very severe noise problem in the transmit signal due to a quality control issue on my unit not seen in others. For a long time they were shipped with the minimum possible flash memory, which soon proved too small for the latest firmware, so a firmware version missing one seldom-used feature, built for early versions of the kit, had to used (at least it includes all the other latest updates). This was fixed a while back, but depending on supplier, you could get one (mine, from a year ago now, is one of those). As far as firmware (software) is concerned, you can easily update that to the latest from the Github site where it is maintained for all versions of the underlying design, (except for one problem discovered in the last couple of weeks!) The software consists of a Bootloader that handles startup and upgrading, and the Firmware, that provides all the features of the radio during use. The Firmware is very easy to update, but updating the Bootloader is a little more intricate and confusing job, involving downloading and running special update software, while going through a few odd steps with button presses and cables. The latest RS-918 could even require that the case be opened and a jumper closed. Normally this isn't an issue, as any Bootloader you'll find in an RS-918 is OK to just leave alone. Unfortunately the developers recently discovered a bug of very long standing in the Bootloader that was subtly corrupting the Firmware on power-up. Recent Firmware versions are particularly hard hit (which is why they finally found it), so to update to latest Firmware, you need to first update the Bootloader (to v5.0.2 or later). Due to this bug's recent discovery, current (Nov/Dec 2018) stock of RS-918s are sure to have older Bootloaders that will need updating. My advice, which I do not give lightly as I respect Amazon and their merchants, is to seek out certain more trusted sources who will either build, test and calibrate an original mcHF radio kit with quality parts, with the latest "mods" (a few people on the M0NKA forum do this in their spare time and are good at it), or go to the RS-918 group/forum and contact Mike, the group owner/moderator, who imports RS-918 radios into the USA and performs tests and calibrations (needed but not typically done at the Chinese factory) to deliver a radio that works "out of the box". Note that Chris, M0NKA, has moved on to a new physical layout (v0.7), and the last version that looks like an RS-918 (v0.6) may not have boards available (Chris made a few "last batches" due to popular demand). The mcHF is an attractive and functional design, but has issues that have been addressed with a confusing series of "mods" and versions over several years. The Chinese "cloners" have not kept up with this history, attempting to "freeze" the design for manufacture, with infrequent changes (good for them on that front!). Because the history of the kit is so convoluted, and assembly so tricky, I'd advise against attempting it for anyone outside a very experienced builder of intricate surface mount kits, willing to dig through a mountain of poorly documented instructions and "mods". (Sorry, and with all due respect to M0NKA and the many people who have contributed to the firmware, but that is my view.) There are even modified and much improved versions of the mcHF under development, most notably by the Germans who are the driving force behind the firmware development. (OVI40 I think it is called). The RS-918 is NOT a turn on and operate radio. At minimum it needs calibration (most hams have the skill and equipment needed), and in some cases, depending on your luck and just how you intend to use it (e.g. with computer control for digital modes), can become a documentation, firmware upgrade, and occasionally even hardware debugging, snipe hunt. It is a great little radio, with "warts", contributed by its origins as a kit and by Chinese manufacturing practices. Expect a learning curve at the least.BTW: Be cautious about Chinese "Upgrades" to the RS-918, such as the RS-928 or RS-978 (I think). One of them will not accept standard firmware (!!!!) and the other has a few more subtle issues. They are another level of crazy above the stock RS-918, and their added features are not worth it right now, IMHO.>>>Original Review - soon after purchase:I'll likely update this review as I "get into" the RS-918 - I'm barely started!.Nothing against either Amazon or their seller, but the situation with the mcHF and its clones is so chaotic that I made my own inquiries for a supplier to ensure getting (for better or worse!) current production from Recent/Quanzhou Risen Electronics. Given the relatively recent date of the firmware, and agreement of appearance and supplied accessories with those listed by Recent, I believe I succeeded.The rig has the dark/printed buttons, and the included accessories were: usual microphone, usual power cable, BNC to SO-239 adapter, small allen wrench (fits shaft screw in VFO knob), 2 sheet metal side "D" handles (nice to protect knobs), 4 longer replacement screws to secure "D" handles, and a very brief one-sheet "Brief Operating Instructions".You could customize your own mcHF build with various upgrades and modifications that you will not find on the RS-918, but the convenience of a (nearly) ready-to-run radio counts for a lot to many of us who don't have the time to navigate the obstacles involved in the build. Chris, M0NKA, is moving on to an improved version, with a new form-factor, and may only produce one more batch of mcHF boards. Life is too short (and I'm too near the end of it!). Fortunately, the firmware development is in different hands and is progressing rapidly, though they are also developing yet another enhanced hardware version. Regardless, they seem committed to keeping firmware compatibility with the mcHF (/RS-918) for the foreseeable future, so the RS-918 should continue to benefit from new firmware for some time.Here we begin to see some of the limitations of the RS-918, though they are not "show-stoppers" by any means. The RS-918 has 192 KB of RAM, while many mcHF's were built with 256 KB. Mine came with firmware 2.5.130, and exhibited a variety of birdies and very oddly behaving noise signals (all with no antenna), that looked to me like DSP anomalies. Indeed, I learned that some recent firmware builds had RAM over-run/overwrite issues that were particularly noticeable in the 192 KB version, which caused receiver noise as well as occasional display glitches. Also, the AGC and traditional S-meter combine to over-amplify internal noise when there is no signal. Fortunately, the developers are aware of the problems and managed to stamp out most of the the RAM overrun in version 2.7.22 firmware (posted only 2 days ago). Bonus, they are working on noise reduction code too!This kind of thing will likely recur on occasion as they insert new functionality and test alternative code without removing the old version immediately. Once the new code gets cleaned up, becomes final, and the old version is removed, this kind of thing should disappear again. Software development goes this way, with new features "rocking the boat" sometimes. 192 KB RAM versions (like the RS-918) may be hit particularly hard, as they were this time.My RS-918 had Bootloader version 3.4.2, fairly recent, so I passed up on re-flashing that and went directly to copying a firmware 2.7.22 .bin file onto a USB flash drive and updating the firmware with a couple of button pushes. It went easily, except for the need to rename the file from "fw-mchf.bin" to "fw-hfsdr.bin", which the radio display made clear was needed.The update "took" and immediately the reception improved, with the odd noise no longer in evidence and the S-meter acting reasonably. As I write this, in the background a group of OM from around the West are having a round-table or informal net of some kind on 80 meters.Another "nit-pick": The power cable appears to be 20 gauge wire, and is fairly long. I wonder if this might present problems on transmit at higher power levels (some versions of the mcHF have transmit issues that are exacerbated by weak power). I plan to make a heavier power cable, once I get a new connector. If I've guessed right, extra power and mic connectors should arrive along with a Christmas present order from Amazon.I noticed that some clones don't list an EEPROM in their System Info menu (mine has 128 KB). If accurate, that means they are using the MCU for parameter memory, and it has much lower write cycle durability than the external EEPROM. It will be written every power down at a minimum, unless the "power-down-without-saving" button combination is used. Whether MCU EEPROM failure is a realistic possibility in finite time I don't know, but early firmware wrote to it needlessly and that was corrected. Because mcHF's have been built without external EEPROM, it is an acceptable variant.While I'm not yet to the point of transmitting (!) because I want to do a few calibration checks first, I did hear of another limitation we are likely to see in the RS-918, involving straight-key CW. While the built in keyer works fine, the RX/TX transition is currently too slow to do QSK (full break-in), or even semi-QSK, with a straight key. Leading symbols are clipped as character speed approaches 20 WPM. Since I'm still learning and can't send reliably at that speed anyway, it isn't an issue. If my speed increases, I'll have to move to a paddle and use the internal keyer (or extend the RX delay to avoid QSK between words). Eventually, they may rearrange the code to remove this latency, as it isn't an intrinsic limitation - but that is not a priority presently.I'll try to come back to this as I use the radio, but so far, I have been pleased with what I've seen. If I've misspoke on some topic, I'm sorry, and I'm sure some civic-minded OM will politely tear me a new one as he corrects the record!I'll attempt to attach some photos of the unboxed radio and the System Info menu.Note that the license information is missing, and that the power-on splash screen (not shown) was very simple. The day-later build date suggests Recent rebuilt 2.5.130 with these changes. Perhaps errors in this editing & rebuilding, and not RAM overrun, caused the very odd receive noise issues. Regardless, a quick and easy firmware update fixed it.

Nice little QRP rig once I was able to update the firmware, which took some tinkering. If you just want a plug and play radio, this isn’t it. But if you’re willing to experiment, learn and work at it, this is a very powerful, versatile little SDR rig.I especially like using it on FT8. Have even made some DX contacts with it. As with any QRP rig, you need a good antenna to complete the picture.I like how lightweight and portable this rig is. I can stuff it in my bag and take it anywhere, even on an airplane.I found the build quality to be just fine. I recommend it.W5FCX

a great little radio, especially for the price point. rx is fine, and i've had decent signal reports on ssb. looking forward to seeing how it does in the digital modes. it uses about half again as much power as ft-817 in rx; i've been powering it with a 12 aH NAPA BlueFuel jump-start pack LiFePo battery, which seems to be a pretty good match serves for all day rx and a about 45 minutes of full power SSB qso. there's lots of flexibility in the open-source firmware.the radio arrived in about 10 days from hong-kong, and has performed as advertised in terms of build quality, etc. it came with zero documentation. upon purchase the maker sent me a link to PDF of manual, but it's for an older version of the firmware. not really an issue, as there's plenty of documentation and support available on the web if you're willing to poke around a bit. if you need lots of customer support and hand-holding, this may not be the rig for you, but if you'd like a fully featured qrp-portable SDR in a handy form-factor for a great price, this should fit the bill for you.

Radio works very well, BUT---The display is not installed properly, it is twisted out of position, and the touch screen does not work properly.

Worked fine out of the box. Neat radio since it does digital modes without anything extra needed. Two points to considerWill not load the latest mcHF due to memory size, however will load 2.7.1. The other point is that your computer needs to be started first before the radio if USB is connected. Otherwise love it.

I sold my 817 for and bought a "Recent 918SSB" and glad I did. First off, I never used the 2 meter or 70 cm on that radio, that is what my dualband DMR ht is for. Second, my operating position is that my head is always much higher than the front of the 817 so always had to tilt the radio way up. The display was so small I needed my glasses and a magnifying glass to see the display. Then when operating CW it is as wide as a barn door, making it nearly impossible to get on the air during busy conditions. I hated the radio, I had it for a year, and every time I used it it worked okay but never enjoyed it.I then got this little Recent918SSB SDR radio! First of all, it interfaces to my laptop with just a USB cable bringing both rig control as well as audio into HRD, Winlink or WSJT. The display is great, the filters are great and if I want I can opt out of QRP. Mine on my MFJ portable meter read 35watts on highest power setting, and lowest 100mw.The sound on the radio is phenomenal and the features are endless.I plan to make up a pelican case to hold everything in one go kit including a small laptop and flexible solar panel. Just love my lil SDR, you just have got to get one of these!

When you clone a clone you get junk....Got 2 both were bad.just suckedThese guys need to fully test these before they sell one.Mine both were susceptible to RF , the AM broadcast band only picked harmonics from 75 meter...maybe yours will work some do. But the ones from here have not so far....

Nifty piece of kit. Tons of features!