FT-817 connector handy hints

I use an FT-817 for my activations complete with the Yaesu softcase. Now working in the electronics field I know that connectors are one of the items almost guaranteed to give problems especially when you start using consumer grade connectors and plug/unplug regularly. I decided that if I was carrying a radio up a hill, I should try as hard as possible to minimise connector wear and make sure any cables had suitable strain relief so that intermittent connections were less likely.

Power connector:

I only had one DC lead which came with right angle plug. I leave the plug in place and run the cable between the radio and the softcase. On the right front bottom of my case there is a loop of material and pop fastener. I keep the extra power cable loosely coiled and held in place by this material and fastener. If you pull hard on the cable (because you stood up to push the aerial back up and caught the cable with your size 18 boots) the pop fastener opens and the cable is released giving some slack. The other end of my power cable terminates in a 5 pin DIN socket. A similar lead from the SLAB terminates in a 5 pin DIN plug. There’s enough slack that I haven’t been able to break the cable yet. I could have used Powerpoles but I had lots of 5pin DIN connectors and no Powerpoles! I have another similar power lead connected to a shack PSU when the 817 is used at home.

Key/paddle connector:

I didn’t want to make anymore holes in the softcase nor did I want to have to remove the radio from the case to plug in the key. I made another extension cable, a 3.5mm stereo jack to cable socket. My kids go through earphones for their MP3 players like mad so I used a cable from a duff pair of earphones. This had a rightangle low profile plug on it and about 1m of thin screened stereo cable. This is left plugfed in permanently and the cable runs between the case and radio like the power cable. I soldered a cable end socket to this thin cable. When not in use, the socket gets stuffed into the strange pocket on the left side of the softcase. The extension cable will coil and fit in there too to keep it safe. This means I don’t have to leave the PalmPaddle cable in place and find some means of protecting the fragile 3pin Molex plug that connects to the paddle proper.

Rear antenna connector:

I only use the front BNC connector so the hole in the case for this has been covered with a piece of sticky tape. It means if you place the radio on the ground then you aren’t going to get bits of soil or sheep’s doings stuffed into the SO239.

Front antenna connector:

I always use the front BNC. I’ve owned a few Yaesu radios over the last 17 years. I’ve found that the two lugs on the BNC socket that hold the plug in place have worn badly. I’ve only seen this on Yaesu gear though. I think they use lead for these lugs! On all the BNC plugs I use with FT-817 I have filed the slots in the plugs to have a less severe profile. Normally the final ‘click’ when you twist the plug on is when the plug is forced into the rubber gasket and rides over these lugs and then is released slightly. This overcentre action is what causes the wear, especially if you use good plugs like Greenpar or Amphenol. Filing the profile of the slot in the plug will reduce the wear on the lugs. This isn’t a problem as the connection is more than secure wihtout being held super-rigidly in place and anyway, we aren’t pushing kilowatts at tens of GHz up the cable.

Finally, when using plugs designed for RG-58 with thin RG-174, there is no effective cable clamping. I soldered up the coax and then using a combination of heatshrink tubing and hotmelt glue, filled in the back of the plug with glue. The heat causes the heatshrink to shrink around the glue. Excess glue is squeezed out and can be removed with sidecutters. The end is a tight water proof connection between the coax and plug body and acts a strain relief.

Hopefully, these ideas will be useful to someone. They’re not super clever, just the result of trying to ensure as cheaply as possible that I end up minimising wear and strain on the radio. Perhaps you have some handy hints or even super clever ideas you’d like to share?


In reply to MM0FMF:
Quote:“when using plugs designed for RG-58 with thin RG-174, there is no effective cable clamping.”

I use BNC plugs that were designed for RG174 - the main one on my antenna is a right angled one so I don’t trip over with my dainty 8 1/2 boots!

Otherwise, couldn’t agree more with your comments. I use a different bag for my 817 (Powerport) and the key sits where a SLA usually sits as it has a feed from the pocket into the bag (what key, I hear you cry!), and there is room to keep the (optional, but I found essential) ferrite ckoke on the power feed if the rig is left in its bag. I use Powerpoles (to be compatible with all the rest of my gear) to connect to the external Li-Ion battery. I think we molly coddle our rigs too much, my one has had a real baptism of fire (and water) but still soldiers on, but it is wise to take care of the obvious areas of concern and Andy’s comments hit the nail squarely on.

Maybe work you this weekend S to S as the weather looks as if it might be kind!


Barry GM4TOE

In reply to MM0FMF:
Quote:“when using plugs designed for RG-58 with thin RG-174, there is no effective cable clamping.”

Hi Andy and Barry
I’ve just bought some plugs from our local ham radio shop here in Glenrothes for the RG-175 coax that i also got they are BNC & also PL259/rg58 with small brass inserts to fit the RG-174 Coax price was realy good aswell the drum of coax 100mtrs was £34 (leoni dacar 100)more info on coax can be found here http://www.leoni-automotive-cables.com/fileadmin/bu/ac/produkte/pdf/en/300.pdf so maybe worth a wee call to bill hi hi

and great user notes Andy on the use of the ft-817 its great to here and read the real users reports very informative

many thanks
Gordon MM3XGP

In reply to MM3XGP:

Have just ‘acquired’ a roll of URM 109 coax and was wondering if anyone had used it for aerial feeder and what their thoughts were. Would need to get a small BNC plug to fit the wire as it is very thin.

73 Glyn