The QRPer Board

After a back and forth about the FT-891 in the comments on QRPer.com, I ended up getting a second hand FT-891 to test out. It came with a mAT-30 tuner, and so far it seems like a nice little rig. My ultimate intention is to explore it for installing on the sailboat, but power consumption has me worried. I was happy to learn via the discussion on QRPer.com that the 2amp receive power draw in the FT-891 specs was not correct, and I find that radio can be dialed down such that it draws about 900mA. Not great compared to my QRP rigs, but a workable draw for certain situations. That said, with the mA-30 in active mode (not actually tuning, just on), it adds about 300mA to the load, for a combined load of 1.2 or 1.3A at receive.

Is there an alternate tuner that works well with the FT-891 that does not draw power while on standby? It seems like it should be little to no draw, and not twice what a KX3 uses on receive just to power the tuner.

Also, I was checking the firmware on my radio and it left me scratching my head. Yeasu lists the following as the the latest firmware:

Main Version 01-09
DSP Version 02-04
LCD Version 01-01

However mine is shown below and appears to be versions that don't exist yet that I can find. Any thoughts? Do I have Beta firmware?

Main 01-10
DSP 02-05
LCD 01-01

On the firmware question, I found on an FT-891 group that newer radios are shipping with that firmware version, but it is not generally available yet. So that solves that.

I'm not an FT-891 user, but consider an auto tuner with latching relays. They draw current while tuning, but next to nothing otherwise. I have been using an LDG Z-100Plus for almost a year, and am still on the first set of 6 AA batteries. Specs say 100 mW while tuning, then almost no current draw. Good for 125 Watts SSB/CW (less for digital modes).

73 de Brian - K3ES

Thanks Brian. I cant figure out why the mAT-30 tuner is drawing so much power while just sitting there, but with it attached the draw is unmistakable on two different meters. I am starting to wonder if the YaesuFC-50 will be better, but I will need to research that. It is expensive, but its included panels allowing it to mount with the 891 would make it attractive for where it would mount in the boat.

Brian - K3ES wrote: ↑Sat Aug 06, 2022 1:18 am I'm not an FT-891 user, but consider an auto tuner with latching relays. They draw current while tuning, but next to nothing otherwise. I have been using an LDG Z-100Plus for almost a year, and am still on the first set of 6 AA batteries. Specs say 100 mW while tuning, then almost no current draw. Good for 125 Watts SSB/CW (less for digital modes).

73 de Brian - K3ES

Another plus one on that LDG. I wired my power cord for the tuner right into the Power pole that I added to the radio with good results. Both are fed off a 12aH Bioenno in a backpack configuration. I assembled my setup that way three years ago, with good results. I attached the mobile bracket the top of the radio and then used double-sided tape to attach the LDG to the top of the bracket..makes for a pretty compact setup.

As far as your firmware editions, are you from the future?? I should go check mine, I've never updated my 891.

Another happy LDG Z-100 Plus user. I've used it for 26 POTA activations, a field day, and messing around at home on the initial set of batteries and it still works like a champ. I should wire up the cable for PowerPoles like NJ0Q did, but the batteries have been working so well I haven't gotten around to it. It is always quick to match and I've had great results with it. The only time I had problems is when the interface cable I was using went bad, but that was the cable's fault, not the tuner's. Replacing the cable (just a standard TRS) solved the problem. You can also manually tune it without the interface cable. I usually use it with my IC-705 and the interfacing works very well.

If you want a no power option you could get a manual tuner. I have a 4 States QRP 4-S tuner kit on my workbench that I hope to build up soon. I haven't been able to test that one myself yet (haven't built it yet) but internet reports say the thing can match almost anything from wires to downspouts! A bit more fiddly, but no batteries to charge and probably a wider range of matching.

Thanks for that input. I think I have decided that the 891 is not a good fit for me. I am going to find it a new home, and if I get 100W itch for POTAI will get a KXPA100 for the KX3 or KX2. I think I am most happy when doing CW at 5-10W, so more power is probably not worth the effort or expense for me.

The plus for all of this is that my K3 at home draws a lot less power than the 891 and I now have a 20Ah battery that will run that for quite a long time for QRP to low power ops at home when the power is out.