Thank you for this video! I love seeing more attention given to its circuit design, since it’s been cloned so many times and at an affordable price point. Whether TYT or Retevis 9000D, AnyTone 588, Alinco x35, or - as you discovered - Kenwood TM-271A. Especially because of the bands this is available in: 70cm and 2m obviously, plus 220MHz / 1.25m in America, and also 4m and 350MHz-390MHz abroad. It also has a socket for adding a DB9 serial port and repeater capability. It’s an extremely capable design that has a lot of potential for Open Source Hardware cloning just like the retrocomputing scene has done for C64 and Amiga motherboards. I’d also love to learn how to use the FFT function of a DSO to modify these to change their bands. I’m very much looking forward to Part 2 from you.
Question the newer tyt 900d vhf only trans in the 144 to 148 how do you open it up to go outside the band. The older tyt 9000d vhf would transmit on 158 Mhz that I am licensed to use is there a easy band opening trick, thank you friend.
LOL, it's easy to do the alignment on these if you know how and unfortunately I don't know. I have tried every possible front panel button press combination to find the "service menu" with no luck. The only button press combination on power up I could find that does anything was "F" and "P5" which lets you select the frequency range of the radio. Undoubtedly there is a service menu waiting to be found. It's possible it's not a button press combination but shorting out a pin on the PCB while powering up like the Kenwood radios they are roughly based off of.
I have serviced dozens of the TH-9000 radios and have never seen the 19.200 osc off frequency. 99% of the failures were CML chips in the early version resulting in a scrambled display/locked up. Let me know if you need parts/help. N5MRG
I have the older tyt 9000d and the band range lets me go to 158 meg. the new radios go 144 to 148 is there a way to open them up to work on 158 I am licensed to use that freq. Thank You
Do you know the spec of the TCXO in these radios? I'm hoping to replace mine with a more stable one/tune it in to work as a TX radio in an MMDVM DMR duplex repeater
Pretty much all radios like that have a soft pot in a service menu. The days of the screwdriver for basic alignments are over. They send them down the assembly line and the computer does it all.
