Hints on how to calibrate the RS-918 MCHF QRP radio. Power adjustment and PA Bias. Links: github.com/df8oe/UHSDR/wiki/A... Also a Checklist link: groups.io/g/RS-918-HF-SDR-Tra...
You da man! I have followed your link in description and went up one level - wow. The complete manual for the build and operation. With full instructions. I am impressed. You have been a great help in getting me acquainted with my new purchase of this radio. Than you. Subscribed and liked. 73s from NZ, ZL3AXL.
John, this is excellent! I picked up an RS-918 from Connect Systems a few months ago. I’ll check these (and other) settings…I have an RF bench with several GPSDO-guided counters. Jerry Wanger # CS checked the radio before shopping but he didn’t likely do all this. I love the Tune feature…just initiate a Tune cycle without changing anything. I’ve used the RS-918to drive a couple of qrp amps to get 45-60w out. Very fun radio…73 de K4FMH
The RS-918 is a fun radio to play with, I put together a go bag with the little radio. Once aligned it works great for a small inexpensive radio. I like it better than the Xiegu X6100. If you have any questions my email is good on QRZ
Hi John, It's kc2wvb again. I was going to start calibrating with respect to power amplifier & frequency as demonstrated in this video, but I don't think I should muck with how it arrived. 1st Initially I have only used the rig in receive mode & I had both it and my RSP-1A by SDR Play hooked up to the same antenna. The rig when zero beated matches exactly the RSP-1A when zero beated for frequency displayed. 2nd When I went into the PA callibration menu I noticed that bias was set to 50 & to me that looks like some one calibrated it before it was sent to me otherwise I'd expect to see the setting at zero. 3rd I only have a 5 watt dummy load thus I am restricted to what I can do, but after seeing all the power settings had various values set and not to the same settings I thought I bet someone already callibrated these settings. To get a better feel for it I connected a RF watt meter in line with my dummy load and for all power settings up to 5 watts the watt meter said spot on. So, what do you think???? Right now unless I hear otherwise I'll leave it as is and photograph all the settings so as to have a reference should I try to calibrate my self. Thanks.....
@@johnwofford2708 Yes, John I bought it new off an EBay seller that had a 5 star rating and paid about $30 more as I remember because the seller might have been State side. I did shoot 42 photographs which was all the distinct menus such as Standard, Configuration, Display, etc with each one opened to show the individual settings. Every one had precise settings except for Filter Selection which shows unused in each possible adjustment. So, yep, not sure whats up at my end. Wish the seller had given me a clue. And in someone elses words: there is a lot of documentation on this rig, but its often scattered and at times contradictory. Aside from my lingering question it sure is a fabulous receiver, best one I have.
I would recommend at least checking the bias, every 918 is different but 50 sounds high to me. Also, have you tried Nizars new firmware for the 96khz spectrum scope??? His firmware even makes the receiver better.
@@johnwofford2708 I apparently have been using an old 86 page manual that was translated from perhaps Chinese by Google translator. It suffered a bit. The RU-vidr, Hamtech ?, picked one up a month ago and published a link to a manual. On the surface it looks much better than what I had been using. Right now the newish manual is on my phone but in a moment I'll send it to my computer and start going thru it. My general idea at the moment is to reset the PA bias to 0 and take a measurement for amps going into the rig from a battery followed by raising the level till 500 milliamps higher than when set to zero. That should tell me if some calibration was done or not. After this we shall see. I see the Hamtech RU-vidr seems to have videoed all his calibration and I think I will watch each one then take a look at my rig and try to do the same plan as for the PA bias. Unfortunately I bought the orange button model with the different display screen that required alteration to the software. Thus the suggested upgrade in receive might not be available to me yet. I did notice when shooting my photos that I am glad I did that the firmware on my rig is from November 2021. Thanks....
The orange knob model is actually a BS-188 and you are correct, the 918 firmware will not work on the 188. The main calibration is the PA bias because without it set properly the rig will overheat. good luck!
Thanks again John. I received my RS 918 in late November and have only used it for receive up to now because of being too busy to focus on calibration. I have read thru the 86 page manual to about page 40 and just came back to your most important callibration settings video. Either tonight or tomorrow I'll calibrate the PA bias for SSB and make CW identical followed by the PA output. I am a bit curious regarding the PA output callibration in that my dummy load is only 5 watts although I could place a 3 Db attenuator in line too. If I calibrate at 5 watts do all the other power settings just fall in line? 73, kc2wvb
somehow my radio shows a spike on the Spectrum Analyser when PTT is pressed... but nothing is seen on the Websdr... what could be going wrong? help will be highly appreciated!!
Maybe I missed it but I did not see a board version in the checklist??? The Checklist items could vary slightly depending on firmware versions especially if Nizars 96khz firmware is used... But for the most part it should work with any version.
That is correct! To adjust the power, press the PA button. I calibrated my pa with 5 watts of power. Do you believe I'm going about things incorrectly?
As long as you set the PA bias first, then go through the PA calibration for 5 Watts and full output on each band you should be good to go. In the menu on the 2.12.2 firmware there is an option to limit power. I personally would not try to get 15 watts out of the rig, I set mine up for 10 watts on full power.
@@johnwofford2708 When I received my RS918 with mcHF V.0.6 board, it came with RD15HVF1 MOSFETs, which I later upgraded to RD16HHF1. After that change, I'm unable to properly configure the PA Bias to add 500mA. According to the manual, I need to connect a 2k2 resistor from the U18 PA Voltage Regulator between PIN1 and PIN4 to raise the voltage by 1.2V because the RD16HHF1 demands a higher voltage. I'll need to change this as well in order to establish the PA. I'm hoping to work this out shortly. Thank you, 73.
