If you look at any old ICOM service manual for a ic-701 or an IC-211 you can look at the service manual and it will show you in explicit detail how a 3 wire system is used with an optical "chopper" wheel to output two signals out of phase with each-other using simple ttl logic they derive which direction the knob it turned and exactly how much. old old stuff! using a bare minimum of logic, in our heads? we can determine that two wires won't give you enough info for this task, a two year old could tell that.
RE read your own statement .. it makes no sense lol, many engineers would love to see the circuit you use. will you post it??
Two lines. The third is the common one, the ground. But I will look after those Icoms, it seems to be interesting.
It might be too late yesterday to me to not instantly react the three wires vs. two lines thing. If somebody speaks about logical values on an A and B line, they should always be referenced to something, that is the ground, so it is not even mentioned. A 2-pin connector might be the same - sometimes the ground is not mentioned as well. Not always, I admit, because they are mostly used for something else than passing through logical levels, a lot of times the logical ground is different from the chassis because of noises, etc. So we may speak about the same thing.
I'm a little bit late to this party, but I've had one of these radio's for about a year, albeit with the Ailunce brand name, and I thought I'd share my experiences. I'll start by saying as shipped it's not fit for purpose and the factory menu settings require a lot of editing to get it to function anything like it's supposed to do. This is primarily because the firmware is that which was originally written for the McHF SDR project and badly edited. In fact if you were to run a string command on the firmware file you'll see the callsign "M0NKA" appear quite a few times as he was the designer of the McHF QRP SDR radio. When I received my example I checked things like the receiver, which is at best adequate. The transmit side of things is another story. The output power was different on all bands, and the measured current draw was making very little sense in relation to the power output, and the spectral purity, or lack of, was probably the worst I'd seen in any piece of kit intended for the amateur radio market. I decided to approach the radio in the same way I did with my McHF, going through the PA-Bias and power output calibration process, and limited the power output to 10Watts on all bands. This certainly cleaned up the output on the HF bands to the point that my regulator (OFCOM) would be happy. However the VHF and UHF side of the radio could not be fixed this way. The manufacturers have made provision in the factory menu to cater for these allocations but they are not adjustable. This results in 6m, 2m, and 70cm being totally unusable, unless your intention is to multi-broadcast throughout the spectrum. I'm including two spectrum plots. These were produced with 40dB of attenuation prior to the input to the spectrum analyser, at a maximum output power of 5Watt (the maximum available on 2m and 70cm) The spurii only started to reduce in relation to the carrier as the power was reduced below 300mW. There are details available to construct a rotary VFO/Encoder using an Arduino project board. I know there's one YT viewer who has sung the praises of this radio in all its versions. When I questioned his conclusions about the V3 of this radio he was quite defensive, and he didn't do a follow-up review as he said he would. I see he's recently done a "review" of the Version 4, but again this is no more than his typical QVC approach to reviewing.
it requires three lines, you can 're-phrase' it all you want and re structure the English language to suite your desires, but facts are facts you can't do what you say with two wires! LINES 2 and 3 mean NOTHING WITHOUT LINE 1!
You show here what that device really is. A "stolen" open source HAM-Radio project, with much new extensions, which dont fit to the hardware. To that the software got worsen in cause of the extensions. Good job, thanks that you invested time to make this visibel.
I can’t take credit for everything. There are two FB Groups associated with this box of bits, and it was member of the UK group that went through the firmware and noted the origins. There have been a few FW alternatives created by the same person that have made some improvement to the radio but not enough, unfortunately, to make it a viable choice. I think that is an impossible task. Based on the support, or lack of, this radio should not be on anyone’s shopping list. It’s worth noting that the OP of this thread, the same person who has “reviewed” each iteration of this radio has not responded to defend his claims. It’s plain to see he’s happy to receive free samples and sing the praises, and then offload the radios via a UK based amateur radio used equipment forum. When I bought my example I did so with both eyes open, and knowing what I do now about the radio I could not in good conscience give it away. There’s no denying it that in the adverts and claimed specifications it does sound like an exciting product. But when you look behind the curtain the reality is quite sobering. The claimed output of 20Watts is farcical to say the least. On the HF side of things it uses the same devices as used in the original McHF, and then it was recommended not to use beyond 10Watts. It will reach 20Watts on some bands but the resultant output will put you on the radar of your respective enforcement agency. On VHF/UHF the minimal filtering is a joke. If you look at the first spectrum plot I posted you’d be forgiven for thinking I was testing 6m, but in actuality I was testing the output on 2m. You certainly wouldn’t want to connect this radio to a ubiquitous triband vertical antenna. It’s actually quite comical in that on my particular example the boot-up splash screen bares the message that the radio is not intended to be used on transmit.
I know about the mcHF project. I was near in the past to buy a pattern. But after I finished the british MKARS80 kit, i thought about if I want to do nearly the same short after this. Sometimes it can be strange to put it well together. And to the company who manufactured the Q900 device, here is to say that its sad to see, that projects like the mcHF SDR are developed by private persons. And that a company just made a bad clone and sold it like its their own invention for far too much money. The companys didnt do nothing for the development or anything else. So it were private people in the past who made this in their sparetime for less money.
My thanks for taking the time to describe your hands-on experience with this product. Also, my thanks for the comment on the veracity of the OP and his "reviews". Too often these UTOOBers (of every ilk) fail to reveal their association with the vendor or that the products 'reviewed' (sales pitch) were a freebie - to be later sold at some profit to the 'reviewer'. I may watch some of these kinds of vids, but always preform Due Diligence before parting with any $$$. My thanks again.
My wife often criticises me for my obsession of always wanting to look behind the curtain, whether that be technology, politics, religion, pseudoscience… and that includes what incentive a YT reviewer might have to sing the praises of a piece of equipment when it’s as plain as a Bulgarian Pin-Up that it’s seriously flawed.
"You may have seen this radio before, but this is Version 3, with all the bugs and kinks worked out." "My main HF antenna is a Half Wave End Fed for 40M with a 49:1 transformer. I also use a 110uH coil to provide access to 80M." This is a guy who does reviews of HF equipment!
