[600MRG] Relay failure on FT891 at w0yse

[Ed Cole]

Neil,

Not exactly clear what you are referring to FT891 "grounding pin"?  I 
suspect this to be a way to key external devices when your FT891 goes 
into transmit mode.

On my K3 that output is called KEY OUT.

We encounter issues getting components into Tx state when doing eme. 
universally a sequencer is used that stages the transfer to Tx of 
several components in sequence in order to not transmit RF in the wrong 
direction.

I use a four-stage sequencer that:
1. turns off dc power to my preamp
2. switches TR relay to Tx state
3. Enables amplifiers to Tx
4. Keys transmit radio into Tx

Each is separated by several msec delay.

My sequencer is made by Down East Microwave (model TRS).

The sequencer can either by controlled by an external switch or by a 
computer: RS-232 DTR or RTS line or via USB/RS232 conversion cable.

When station power is off the system defaults into transmit 
configuration to protect everything.

Others, such as W6PQL, offer sequencers.

73, Ed - KL7UW

My 630m station made first step toward operation with the raising of a 
80m folded dipole to 36-feet AGL, fed with open ladder wire.  Eventually 
the feed wire will be shorted to drive with a large base loading coil to 
become a top-loaded a "T" vertical.  Too late to lay ground radials this 
year as temps are going below 32F in daytime (and snow not far off).

Ground radials will be placed on the ground held by wire staples 
(obtained from DX Engineering).  This will hold wire below mower blade 
level.  Green insulated No. 12 THHN is being used.

On 10/19/2023 2:33 PM, Neil Klagge wrote:
> Well, a new wrinkle in my quest to make a QSO on 630m this fall/winter.  
>   My T/R relay wont work because the TX-grounding pin in my FT891 quit 
> working. Probably bad contacts on the internal relay in my radio.
> 
> Now the only way I can switch between my RX active loop and my MF TX 
> antenna is by a manual switch. That will eventually be a problem the 
> first time I accidentally put some RF into the active amplifier at the 
> RX loop.
> 
> I am about ready to give up on 630m after this major setback. At this 
> point I can either RX or TX but not both without possible damage to the 
> loop.
> 
> I have looked at some of the MFJ RF switches but none of them seem to be 
> right for my situation.
> 
> Hoping to get some inspiration from above....
> 
> 73
> 
>>> **´¨)
>>> ¸.•´¸.•*´¨) ¸.•*¨)
>>> *
>>> *(¸.•´ (¸.•`   Neil *, wØyse, DN41ah, North Ogden, Utah 84414
>> BCC: Gene & Stan
> 
> ______________________________________________________________
> 600MRG mailing list
> Home: http://mailman.qth.net/mailman/listinfo/600mrg
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:600MRG at mailman.qth.net
> 
> This list hosted by: https://www.qsl.net
> Please help support this email list: https://www.qsl.net/donate.html