Yaesu: Inexpensive wall power for FT-817/818

[tweiss3]

So, to reduce the things I carry around every day, I have taken my FT-817 from it's dusty place on the shelf, and found a place on my desk where it is within reach, and I can hear it on very low. My problem now is the internal battery has limited life, and I'd like to find a permanent power source that doesn't take up much space. I currently have the windcamp power pole adapter to keep from breaking the barrel connector/port.

I tried a 12V 5A laptop style power supply, but it was incredibly noisy. Goes from S3-4 to S+ on the meter, can't hear anything. Unplugged I can hear plenty well with the S4 noise floor. As soon as I disconnect that power (still plugged into the wall) the noise goes away. 5 clamp on ferrites did nothing (2 large enough to get 3 wraps in each).

Looking at small desktop power supplies at DX, they cost more than I anticipated ($140), and seem larger than I'd like to carve out a space for.

DX now carries Bioenno batteries, I could get a 3Ah with charger for about half ($80) the cost of a power supply. Is that a better option? Any huge downsides to leaving it plugged to the charger?

The radio only needs 2A, so 5A would be plenty. Any other ideas worth trying?

 

[vagrant]

Radio Shack 3A pwr supply. $25 w/free shipping

Pardon Our Interruption...

 

[Hit_Factor]

Charger is probably noisy too. But, if you charge while not using the radio it might not matter.

Bite the bullet and get a linear power supply. Switching power supplies can be noisy.

Be sure to check peak amperage and continuos amp rating for radio and supply.

 

[tweiss3]

Radio Shack 3A pwr supply. $25 w/free shipping

Pardon Our Interruption...

That's the ticket.

 

[prcguy]

Many years ago this company came up with a low RFI portable supply for the Elecraft KX3 series and it can be adapted to many other radios. I have one I use on my KX3 and Icom IC-705 and it’s very RF quiet.

Kx33 Low-RFI AC Power Supply for HF Transceivers - Pro Audio Engineering

proaudioeng.com

 

[wa8pyr]

Radio Shack 3A pwr supply. $25 w/free shipping

Pardon Our Interruption...

Good idea. Any decent linear power supply with good filtering and regulation would be better than a switching supply. The later Radio Shack supplies were pretty good.

I was using good, well-designed low noise switching supplies in the shack at home, and they worked well; however, when I switched to a linear supply there was a noticeable drop in the received noise.

 

[vagrant]

Switching power supplies have improved and I use them, where acceptable, but I also use a linear power supply. The cost difference for improvement is understandable, but the OP is looking for a lower cost. The one noted by prcguy is something I would go for over the RS model I linked, should I need one in the future. In particular, the small size and weight are also factors that put the ProAudio Eng. power supply on my perspective list.

Alternatively, I use various LFP batteries. A 12.8v 10 Ah LiFePO4 battery would handle 2Ah current and keep it friendly with the 0.2C draw providing years of cycles. The small LFP charger for such a battery is also tiny and light. Just top it up while sleeping. This option provides for portable use as well.

I would not purchase the Bioenno battery, especially that low 3Ah. The cycle life will be impeded by the power draw, even @ 2Ah. For less than $80 one can easily source a 16Ah LFP battery and a 2Ah LFP charger via Amazon. The 16Ah will also provide plenty of “field time” away from mains AC. That is for low current radios. For 100W radios use a 100Ah battery and a 20Ah charger and or solar with the proper controller of course.

 

[Sparkchaser]

So, to reduce the things I carry around every day, I have taken my FT-817 from it's dusty place on the shelf, and found a place on my desk where it is within reach, and I can hear it on very low. My problem now is the internal battery has limited life, and I'd like to find a permanent power source that doesn't take up much space. I currently have the windcamp power pole adapter to keep from breaking the barrel connector/port.

I tried a 12V 5A laptop style power supply, but it was incredibly noisy. Goes from S3-4 to S+ on the meter, can't hear anything. Unplugged I can hear plenty well with the S4 noise floor. As soon as I disconnect that power (still plugged into the wall) the noise goes away. 5 clamp on ferrites did nothing (2 large enough to get 3 wraps in each).

Looking at small desktop power supplies at DX, they cost more than I anticipated ($140), and seem larger than I'd like to carve out a space for.

DX now carries Bioenno batteries, I could get a 3Ah with charger for about half ($80) the cost of a power supply. Is that a better option? Any huge downsides to leaving it plugged to the charger?

The radio only needs 2A, so 5A would be plenty. Any other ideas worth trying?

When I was deployed to the Big Sandbox, I took my FT-817 with me, powered it from a discarded 12 volt car battery, which I trickle charged with a 12 volt wall wart, went on the air locally licensed as 9K2/KD7OKY and had lots of fun on 20 meters. I would just unplug the charger during operations, and go for hours! Zero cost!