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Author Topic: FT-891 QRP  (Read 664 times)

N8TI

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FT-891 QRP
« on: March 29, 2021, 02:52:34 PM »

I have been out of the radio buying market amd was going to get a FT-818, but when I looked at the features of the FT-891, I decided to go that way. Yes, it does take about 2 to 3 times the power requirements on receive and is pretty thirsty on transmit, even in low power, for park Punic tables or out on the back deck, I think it will do quite well for QRP operation into an endfed random wore when paired with an antenna tuner, of which I have many.

What made my decision were the reviews that said it had a real nice receiver. Plus, it has a lot of features if you learn the menus.
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WA6BJH

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Re: FT-891 QRP
« Reply #1 on: March 29, 2021, 03:11:04 PM »

“for park Punic tables.”  I love the way our computers correct our typing mistakes.  That one’s really good.
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N6MST

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Re: FT-891 QRP
« Reply #2 on: March 29, 2021, 03:22:20 PM »

If you're going to be lugging large batteries to the park anyway you would have been better off with an IC-7300.
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AJ6KC

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Re: FT-891 QRP
« Reply #3 on: March 29, 2021, 05:13:43 PM »

It seems like a very reasonable choice:

https://youtu.be/U1bqp3C3s9Q

In this video it looks portable and performs well. He’s using a small 20AH battery. I have an FT-891 but I’m planning to use it “mobile” and install it in my Toyota Tacoma. If I can find some sort of quick disconnect rack I could still use it as a field radio too.
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K4FMH

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Re: FT-891 QRP
« Reply #4 on: March 29, 2021, 05:33:20 PM »

I have been out of the radio buying market amd was going to get a FT-818, but when I looked at the features of the FT-891, I decided to go that way. Yes, it does take about 2 to 3 times the power requirements on receive and is pretty thirsty on transmit, even in low power, for park Punic tables or out on the back deck, I think it will do quite well for QRP operation into an endfed random wore when paired with an antenna tuner, of which I have many.

What made my decision were the reviews that said it had a real nice receiver. Plus, it has a lot of features if you learn the menus.

I also use the FT-891 for portable ops. I use a Bioenno Life4Po 20aH battery in a Red Oxx Lil Roy case...room for the charger and a Tenergy power meter. The 891 is in a soft Gator Case made for wireless mics.it’s an easy to use combo. The Rx amp draw as stated in the Yaesu specs is operationally inaccurate. Mine has never gotten close to even 1 amp.

I also use an MFJ 939Y ATU which draws power from the 891. It’s also in a Lil Roy. My Wolf River Coils TIA portable vertical is in a small padded camera tripod case bought on Amazon for $16. This combo of four small cases sounds like a lot to carry. Except it’s really not. Grab and go.

I’m glad you’re pleased with yours. I have several other portable rigs. I pick up the 891 combo most of the time.
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N8AUC

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Re: FT-891 QRP
« Reply #5 on: March 29, 2021, 05:56:39 PM »

The FT-818 has it's place, and it's a nice rig. I've got an FT-817 and love it.
But, it needs added filters for decent selectivity though.
Unfortunately, the Collins Mechanical filters aren't being made any more, so the add-in filters are getting tough to come by.

But the FT-891 is a REALLY nice rig as long as you don't need VHF and UHF coverage.
And it's got IF level DSP, so no extra filters are needed.

I would have no hesitation running an FT-891 and carrying a bit more battery capacity to run it
I know several folks who have one, and they absolutely love them.

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N8TI

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Re: FT-891 QRP
« Reply #6 on: March 30, 2021, 09:43:52 AM »

N8AUC’s setup looks great. I will simply copy it since he did all the work figuring out how to put the setup together. I have a LDG antenna tuner  that has always worked well. I looked at the Wolf River stuff and  it looks real nice, especially the ability to center load the antenna with their mini coil. Real nice. I like their larger tripod.  Some nice Wisconsin machining work. Real cool. Getting excited about doing some CW portable operations.
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K6AER

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Re: FT-891 QRP
« Reply #7 on: March 30, 2021, 11:30:54 AM »

I don't have access to a FT-891 but did some measurements on m IC-7300 which should be about the same in current draw. I did some current testing.

Supply voltage was 13.4 volts

Receive current was .86 amps at normal speaker audio.

Key down CW carrier was 6.9 amps at 5 watts out.

SSB audio on transmit at 5 watts peak out was 4.7 amps

Generally speaking, in portable operations, you are receiving about 70% of the time. This gives you and average current draw of 2.0 amps per hour. A 20 AH battery should be fine for a day of portable operation. Add a portable 20 watt solar array and you could operate well into the night.

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K6AER

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Re: FT-891 QRP
« Reply #8 on: March 30, 2021, 12:13:28 PM »

Just out of curiosity, I checked my IC-718 that I use for portable operation.  Receive current was about the same as my IC-7300 and was .82 amps. The transmit current in SSB was about 4.0 amps at 5 watts PEP and was a bit less than the IC-7300 but that was probably due to the IC -7300 having a stronger audio compression on transmit. Most 100-watt radios will be fine for portable QRP operation.  The largest current draw is on transmit and is not much more than a small QRP radio

The FT-818 list the receive current as .45 amps and the 5 watt transmit current at 2.7 amps. Not a lot is gained by using a strictly QRP radio other than size and wow factor.

If you need a good AGM batter for portable operation the Walmart 30-amp batter, ES-TX30LA, sells for a bit under $70. I use than batter for portable operation and it will last all day at the 15-20-watt output level.
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K4FMH

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Re: FT-891 QRP
« Reply #9 on: March 30, 2021, 01:50:58 PM »

I don't have access to a FT-891 but did some measurements on m IC-7300 which should be about the same in current draw. I did some current testing.

Supply voltage was 13.4 volts

Receive current was .86 amps at normal speaker audio.

Key down CW carrier was 6.9 amps at 5 watts out.

SSB audio on transmit at 5 watts peak out was 4.7 amps

Generally speaking, in portable operations, you are receiving about 70% of the time. This gives you and average current draw of 2.0 amps per hour. A 20 AH battery should be fine for a day of portable operation. Add a portable 20 watt solar array and you could operate well into the night.

Your current draw measurements on RX are very similar to mine. I’m not a CW op so the TX would differ. When I asked on a Yaesu list why the engineering specs were significantly higher than in practice, the Sales Mgr went ballistic saying it wasn’t a buyers business as that was engineering. I commonly read posts in various places by prospective buyers of the 891 for battery (portable or EmComm) use that it won’t work because of the excessive Rx battery drain. So much for it not being a buyer’s business, lol.
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N6MST

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Re: FT-891 QRP
« Reply #10 on: March 30, 2021, 03:50:15 PM »

the Sales Mgr went ballistic saying it wasn’t a buyers business

This is unacceptable. Name and shame, please.
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K0UA

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Re: FT-891 QRP
« Reply #11 on: March 30, 2021, 05:25:52 PM »

It seems like a very reasonable choice:

https://youtu.be/U1bqp3C3s9Q

In this video it looks portable and performs well. He’s using a small 20AH battery. I have an FT-891 but I’m planning to use it “mobile” and install it in my Toyota Tacoma. If I can find some sort of quick disconnect rack I could still use it as a field radio too.

I use one in my mobile, but I made my own steel U shaped hump mount.  Just cut slots in the top for the 4 screws to hold the radio. Then substitute the screws with thumb screws found on amazon. It comes out pretty quick. I use Anderson power poles on the short power cord so that comes apart quickly and unscrew the PL259 and you have a portable rig.
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73  James K0UA

AJ6KC

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Re: FT-891 QRP
« Reply #12 on: March 30, 2021, 05:43:52 PM »

I do use Anderson powerpoles and plan to use a separation kit to place the control head on my dashboard and the body in the back of my cab. Any chance I could see a picture of how you did this?

I use one in my mobile, but I made my own steel U shaped hump mount.  Just cut slots in the top for the 4 screws to hold the radio. Then substitute the screws with thumb screws found on amazon. It comes out pretty quick. I use Anderson power poles on the short power cord so that comes apart quickly and unscrew the PL259 and you have a portable rig.
« Last Edit: March 30, 2021, 05:49:47 PM by AJ6KC »
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WB6BYU

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Re: FT-891 QRP
« Reply #13 on: March 30, 2021, 05:53:45 PM »

Quote from: K6AER
Just out of curiosity, I checked my IC-718 that I use for portable operation.  Receive current was about the same as my IC-7300 and was .82 amps. The transmit current in SSB was about 4.0 amps at 5 watts PEP...

...The largest current draw is on transmit and is not much more than a small QRP radio

The FT-818 list the receive current as .45 amps and the 5 watt transmit current at 2.7 amps. Not a lot is gained by using a strictly QRP radio other than size and wow factor...




It does, of course, depend a lot on your particular
application.  My first QRP rig drew 450 mA... on
full transmit.  My Argonaut was happy with a 1 amp
power supply.  I have another rig that draws less
than 25 mA on receive.

A 4.5 Ah gel cell would run any of them for a full
day contest, or a week-long backpacking trip. 
I certainly wouldn’t want to have to carry a
bigger battery (though lithium cells would be a
better choice these days).

That’s not to say that there is anything wrong
with using a high power rid at QRP levels.
But there are cases (such as when you have
to carry the station a significant distance) where
low current consumption is important for
minimizing weight.  Of course, the weight of
the radio gets factored into that as well.

N8AUC

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Re: FT-891 QRP
« Reply #14 on: March 30, 2021, 07:57:12 PM »

I don't have access to a FT-891 but did some measurements on m IC-7300 which should be about the same in current draw. I did some current testing.

Supply voltage was 13.4 volts

Receive current was .86 amps at normal speaker audio.

Key down CW carrier was 6.9 amps at 5 watts out.

SSB audio on transmit at 5 watts peak out was 4.7 amps

Generally speaking, in portable operations, you are receiving about 70% of the time. This gives you and average current draw of 2.0 amps per hour. A 20 AH battery should be fine for a day of portable operation. Add a portable 20 watt solar array and you could operate well into the night.

That's similar to what I do for Field Day the last few years.
I run my FT-857D off of a 42Ah AGM battery box (21 Ah usable capacity at 50% DOD).
It's built into a fairly small plastic tool box I found at Home Depot. Has a bi-directional ammeter
in the box, a voltmeter, and an assortment of connection methods from binding posts, to a
cigarette lighter socket, and a couple of Anderson Power Poles as well.
Use a set of Harbor Freight Solar panels to keep the battery topped off during the daylight hours.

My FT-857D measured current draw is about 500mA on receive, and 2A transmitting at 5W output on CW, 4A at 20W, and 5.5A at 30 W. I usually keep it set at 20 watts out. Runs all night long on that, and when the sun comes up on Sunday morning, the battery starts recharging from the solar panels. By the time we stop operating at 2PM local time, the battery is almost fully recharged.

An 817 or 818 with that power arrangement would be like a little kid with an all-day lollipop.

I saw a guy on you tube the other day who built an 80 Ah LiFePO4 battery box in a plastic ammo can. That just might be my next construction project.
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