Antenna Tuner Pinouts for Yaesu

[K7VZ]

Both the Yaesu FT-897D and FT-950 have a Tuner 8 pin port on the back. I have the LDG YT-100 automatic antenna tuner and cable that works with the FT-897D. I was trying to figure out if it would work with the FT-950 radio. See screenshot below.

1. What are TX D and RX D? It looks like they are reversed?
2. What is BAND C? Is that the same as Tuner Sense?

I had to flip the one image to get them to orient the same way.
http://i687.photobucket.com/albums/vv231/k7azv/TunerOutput.jpg

[AC0VH]

Did you ever get this solved? I am making up a cable for a FT-950 to FC-40. Wonder who at Yaesu thinks 15 feet is ever long enough? I started beeping out the cable that came with the FC-40 and it seems like it's straight through, but like you mention the schematics look like 4 and 5 should be crossed in the cable. That makes sense to me in a traditional serial cable sorta way.

FWIW, I did temporarily hook up the FC-40 and with the included cable it ran through a tune cycle, although I didn't have enough time to do much more than notice that the band noise went up, so I assume it found a tune.

[K7VZ]

No, I was told that the CAT commands are different from the 897 to the 950, so even if I had a cable with correct pinouts, the LDG YT-100 would not properly tune on the 950. My solution has been to "dual tune" using the 897 first.

Setup is something like this.
Antenna --> LDG YT-100 --> A/B Coax Switch --> A is 897 / B is 950.

So if I want to work 40m, I turn the switch to A and the 897 to any frequency in the 40m band. Run the tuner and then shut the 897 off and flip the coax switch to B. Now, the YT-100 tuner retains that setting and I'm able to tune again with the internal tuner in the 950 as I move up and down the 40m band. That works in the short term. My plan is to get a better antenna up that has a 3:1 match unlike my G5RV Jr.

[AC0VH]

That sucks. FWIW, I was looking at the BetterRF Yaesu Tune Control, which is a box that adapts the tuner port to a generic screwdriver or tuner control. This was made for the 857, 897 and FT-100 but can be made to work with the 450 and 950 by shorting pins 3 and 6, which looks to put the reset level on the tuner sense. Apparently people have been able to make other LDG tuners work using this box.

http://www.betterrf.com/yaesu-tune.html
http://www.betterrf.com/450_950Mod.pdf
http://www.eham.net/reviews/detail/4816

[K7VZ]

For the 897/857, the LDG YT-100 works awesome. I love it. It's just a bummer Yaesu had go go and change things on the 450/950. Leonard asked the question on the LDG Yahoo group for me and there is an LDG tech on there who answered. They basically are not cross compatible because of the changes Yaesu made in the CAT commands. That's why LDG came out with a separate YT-450 to work with those radios.

[AJ4ZV]

I was looking a picture of the YT-100 and saw a tune button. With the tuner hooked up to power, is it possible to key the radio in cw mode and hit the tune button on the tuner to make it tune?

[AC0VH]

Not that it helps you Virgil but to complete a thought...

I just got done building a 40' tuner cable and it's definitely a straight through cable, pin 1 to pin 1, etc.