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  1. YaesuFT847
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RX-only HF mod?

 

Hey all, just found this group. Maybe this is a stupid question but bear with me. Is there a way to get RX-only on HF (or disable TX on the the antenna port)? I don’t use HF much in my 847 and got the idea to maybe hook that antenna port up to the RX-out on my FTDX3000. But I don’t want to fry it by accidentally keying up my FT-847.

Is something like this viable? Or should I just buy another receiver like I was planning to do before I got this idea…

thanks!
John
KB0GGS
 

I believe that applying 5 volts to pin 8 of the tuner socket will inhibit TX.

I am at a loss though to understand why you? would want to use the 847 for RX, when the 3000 is arguably better at RX on HF.

Also, if the FT3000 is being used for TX, you will be overloading front of FT847, surely?

Why? not just swap antenna feeds in to 847, and use that, with 3000 turned off? Seems much easier.

?

Andy
 

I tend to agree here, the FT 847? was never the best for HF, you could change all the pin diodes, you could also fit 10 to 15dB attenuator, this will help on RX, and also help when the Tx is on the 3000.

Most TX/RX change over relays only have 12 to 15dB isolation. You cold also fit some back to back diodes on the RX path

73 Andrew

Get

 

Thanks guys, sounds like it might not be worth the trouble. The idea is to use a secondary receiver with the 3000, not instead of it. Why? Might be handy in contests, but mostly just because it’s possible ?

It will probably be easier and safer to just use a dedicated receiver for this.?

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