Walt - thanks for sharing your enthusiasm. Looking forward to you putting it on the bench and checking real power vs indicated and some S/N measurements.
Yes I will absolutely be on the beach with this rig. I'm curious as well on the real power output as well as other metrics. I'll be checking that soon.
Good to hear. The same maker had sold the FX-4 via LNR Precision. (FX-4 – LNR Precision Inc) The even earlier FX-2 (FX-2 – LNR Precision Inc) (2012) was also plagued by ongoing problems which ended its career early as well. Folks in posted reviews seemed to be happy with the rigs, once everything was sorted out. I suspect the infamous "use the buyer as a beta tester" - so often seen in full price ChinaRadios, may be what killed the earlier versions. John, @AE5X, certainly was open about the issues he found. I appreciate that kind of openness here on the Zed. While I had actively sought an FX-2, I found the (tr)uSDX filled my itch for a tiny radio....with better support, full documentation and a larger user community.
I activated K-0034, Great Smoky Mountains National Park with the FX-4CR and I have to say the noise floor was great. I heard stations I would never come close to hearing at home in the Chicago suburbs. For SSB my noise floor is around -127 dBm. I also checked the S-meter and the calibration is spot on. The radio also has some level of BCI filtering. I cannot run the 1.2 firmware and had to go back to 1.1 because the software developer increased the audio compression to where the transmitted audio is distorted on SSB. The form factor is great for POTA in my opinion, recently replacing my G90 for that role. I did have my USB interface go bad and Yu sent me a replacement board that resolved the issue.
Nice video. Impressive QRP DX performance from a radio that fits in the palm of your hand! Love the 20 watts! This is what every portable QRP radio should have. Especially helpful when band conditions are in the tank. Bluetooth is a nice touch. I have a few portable external Bluetooth speakers that would sound really good with it. I guess you could also use Bluetooth for CAT control with logging programs. Does it have general coverage receive, or just the ham bands? Can you turn the Bluetooth feature on and off, or is it always on? Current draw specifications during RX / TX? I don't see any documentation about its in-depth features, but I didn't really do any extensive searching and digging around either though. The website doesn't appear to have very much information about it. Just production status information is all I could find.
If you put it in Rx only mode you can tune the entire frequency range. You turn off Bluetooth if you want to use USB, or just because you do not need it. RX is around 200 mA draw, TX depends on mode/power and I have not done much in the way of testing. The manual could be more exhaustive.
I did find the earlier FX-4C Operators manual. FX-4C English Manual (K6ARK v0.2).doc (wsimg.com) Impressive for a ChinaRadio product. Zero technical data or even a schematic. A schematic without logic states/etc would likely useless for most SDR type rigs anyway. It would seem they have a hit on this iteration.
Hiya I brought a trusdx low and then built a trusdx classic. I’ve also owned an x5105 and borrowed an x6100 all intended for portable use on multi day unsupported off trail hiking trips I’ve now got the fx-4cr and it’s world apart better than the others specifically for SSB voice operation. I’ve a Yaesu ft857d which I think will always stick with me and I suspect the rx audio on the FX-4Cr is better. The support certainly is much better than Yaesu’s. The 20w on the fx-4cr seems to cut through the noise better than the yaesu at 20w too. to refer to this as a “Chinese rig” in a derogatory manner is simply wrong and whilst I acknowledge the generalisation this is an exception of note also look carefully where most components are manufactured in the main brand rigs. I can honestly say this is an incredible unit and on opening it up the attention to detail is superb especially in your intended us is backpacking the toroid windings are not going to move regardless of how the radius manhandled.
