#115636

This is kind of a continuation of the display thread/subject. I received the display yesterday. It came with the mini DIN cable and my 817 was able to power it. However, I am using the cat port for the LDG Z817 tuner with radio menu setting at 38400, the new display requires a cat rate of 4800. The LDG tuner has a pass through cat. Not sure how to make both work. Can I just set to the lower rate, 4800 and both will/should work? There is also a RJ45 connection option that I haven’t tried yet. Thanks all

#115637

开云体育

Hi Michael,

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If I’m not mistaken, the tuner only uses the Band Data pin from the radio to tell it what band you’re on (plus Gnd and power, of course).

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The CAT Tx and Rx pins are different pins and, to my knowledge are not used by the tuner at all and are just passed through to the socket on the tuner.

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Therefore, it should not be a problem to change the data rate for the CAT port to 4800 bps.

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73….Eric VK2VE.

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Show quoted text

From: [email protected] <[email protected]> On Behalf Of Michael Davis via groups.io
Sent: Tuesday, 31 December 2024 02:56
To: [email protected]
Subject: [ft817] FT817 compatibility

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This is kind of a continuation of the display thread/subject. I received the display yesterday. It came with the mini DIN cable and my 817 was able to power it. However, I am using the cat port for the LDG Z817 tuner with radio menu setting at 38400, the new display requires a cat rate of 4800. The LDG tuner has a pass through cat. Not sure how to make both work. Can I just set to the lower rate, 4800 and both will/should work? There is also a RJ45 connection option that I haven’t tried yet. Thanks all

Virus-free.

#115638

Unfortunately, the Z817 does use proper CAT commands to set the FT81x to low power transmit when tuning. It's fixed at 38400 baud, so the pass through won't work for the OP.

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You can use the Z817 as a tuner without the CAT cable, i.e. connect the display directly to the radio.?

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Full detail in the Z817 instructions...

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Regards

John G0GCD

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#115639

The Elecraft T1 only uses the analogue voltage band data. I made up a splitter cable with 3.5mm jack and TTL RS232 converter to 9 pin serial for CAT (which works with a USB adaptor).

I set the FT817 manually to low power for tuning as I'd want to check SWR safely after tuning. I've done that with every radio forever and even with the FTdx10 & FC40, so after tuning I check SWR at low power. If the LDG uses the analogue band data then the internal connection for CAT could be removed to have pass-through.

#115640

Thanks Eric. I think I understand your reply. Yes, I can change the CAT rate to 4800 in the FT817 menu and the display will work when connected with the mini din cat cable. The Z817 tuner requires a cat rate of 38400 and will not operate at 4800. I'm wondering if I use manual tuning, by keying rhe radio on packet, AM or CW and not going to lower power, what would be the danger to tune into a mismatch until the tuner matches the rig to antenna? I sure don't wat to blow the finals at 5 watts. I know your answer, if "it's ok" would not be a guarantee of no damage.?

#115641

John, thanks.. I'm wondering if I use manual tuning, by keying the radio on packet, AM or CW mode and not going to lower power, what would be the danger to tune into a mismatch until the tuner matches the rig to antenna? I sure don't wat to blow the finals at 5 watts. I know your suggestion, if "it's ok" would not be a guarantee of no damage. I'll read the Z817 instructions again. I was hoping that with the tuner connected between the radio and antenna there just might be some kind of protection.?

#115642

Mike, I'm glad you are doing the tuning in low power out of habit. Not sure what you mean about removing the internal connection for CAT. Thanks

#115644

If the LDG only uses CAT to set power and uses the analogue band voltage to know band, then CAT could be disconnected? But maybe it uses CAT to read the frequency. I don't know.

As an aside: I added a bargraph IC to my homemade linear for the 817 to select the relays for the band filters on the o/p of the PA and had pass-through CAT sockets.