ARCHIVE: Australian Ham Radio Discussion Forum ( AHRDF )

Recently the Ni-MH battery pack for my FT-60R has decided to show signs that it is on it's way out.  It's 6 or 7 years old so I am not too unhappy.

I have a AA battery pack lying around so I decided to put it to use.

I filled it with alkaline AA's and the FT-60R sprang to life.

Now I have a couple of AA sized lithium 3.6v (primary) batteries that are surplus to requirements.  3.6 + 3.6 = 7.2v - it adds up!

If you look at the attached image you can see I have inserted them into the battery pack and the black jumper bypasses the missing battery slots.  At the terminals I get 7.3v.  Seems good.

When I load it into the radio nothing happens.

So I took out the lithiums and put the alkalines back in. I then used the green and yellow jumpers to attach the battery pack to the terminals in the radio and, as expected, the radio worked.

I removed the alkalines and refitted the lithiums and the black jumper.  Attached the green and yellow jumpers to the radio terminal - nothing.

I then connected the green and yellow jumpers to a small LED board which lit up merrily. So the batteries work, the case works, the radio works it's just that the batteries, case and radio won't work together.

Could the FT-60R be looking at the power source and deciding that the internal resistance (or something) of the batteries is out of spec and goes into protection mode or something?

I mean it's not a hard thing - some batteries, a case, some wire and a radio, what could I be missing?

User manual :   Page 12 states that you cannot use NiCAD or NiMh cells (and undoubtedly LiIon too) in the FBA-25A battery holder.

https://www.yaesu.com/downloadFile.cfm?F...tion%2Fpdf

It may be that there is yet another extra contact jumper is needed, the schematic might tell you.

The third jumper for charging is basically the outside shell of the end battery, which in this case is not connected and also not connected for AA's.

It concerns me that I can run the radio with AA's with the battery pack external to the radio, thus avoiding the charge circuit but not the lithiums.

Reading elsewhere shows many folk using rechargeable li-ions with the radio -charging issues notwithstanding, the difference here is that these are lithium primary batteries. I have some 3.7v AA Li-ion rechargeable batteries on their way from Singapore. I guess I'll see what happens with them.

It is curious that the radio seems to detect them and refuses to turn on.

I might try to cobble up a cable and plug it into the external DC port.

I use a 2 cell Li-Po in my FT-60. I don't charge it via the radio but it works fine.
Charging is done by removing it from the radio and plugging it in to a Li-Po charger.

[attachment=323]

That's kind of what I was trying, but the radio doesn't like the lithium primary cells.

I am awaiting so li-ion rechargables and some ni-mh as well. We'll see what we see when they arrive from Singapore.

An update:

After a very quick delivery of some Ni-MH AA rechargeable batteries (< a week).

I have charged them up an put them into the AA case. It all seems to work like it should.

I am still waiting on some Li-ion rechargeables to see what difference they make to the conundrum.

At the very least these ni-MH batteries (cells?) should be a fair replacement - they claim to be 3000mAh so the pack should equate to 18,000mAh or 18 Ah which is a far cry above the original 1800mAh of the Yaesu pack.

(18-06-2019, 04:00 PM)VK2CSW Wrote: [ -> ]At the very least these ni-MH batteries (cells?) should be a fair replacement - they claim to be 3000mAh so the pack should equate to 18,000mAh or 18 Ah which is a far cry above the original 1800mAh of the Yaesu pack.

Putting batteries in series does not alter the AH capacity.

Ah yes, there is that.

I confused myself...

Still, 3000mAH is still more than 1800.

Colin,
You could also try getting some blank AAs to use with the '3.7V batteries, would eliminate and problem with wiring etc.

A idea I was going to investigate for my HH

73 from Michael

VK6TU

You know, I used to use blank AA's in underwater camera strobes when using carbon batteries in place of NiCads.

I wonder where they went.

They must be in a box somewhere...

Thanks!

Forgive me "necroing" this thread. I have finally worked out the issue.

As I am sitting at home with "Catastrophic Fire Danger Rating" outside I decided to charge up the HT's and once again came across this issue.

This time I have a solution!

The 3.7V lithium batteries are ever so slightly thicker in diameter than an AA alkaline. Not enough to prevent them fitting into the AA carrier - or so I thought.

In the previous attempt I modified the carrier so only the top two slots (of six) are in play. If I put in the lithiums and measure the OC voltage at the contacts I get 7.2V. All good.

When I put the carrier into the radio, nothing, nada, zero, zilch.

Maybe the contacts on the ebay carrier are dodgy? I duly beefed up the contacts with some foil. Still nothing. I had been through this before...

Then I made a fortuitous mistake. I forgot to turn the radio off as I removed the carrier. The radio briefly came to life, well, until the carrier was removed.

So new experimentation ensued.

It turns out that the extra diameter of the top cell was causing some tension as the carrier was snapped home. This tension pushed the cell back against the spring which inserted an air gap between the positive terminal and the carrier contact. Wedging in a bit of foil closed the gap and Hey! Presto! the radio came to life.

I hope that helps others!

Here is a quick image of the wiring mod to the battery carrier.

Not withstanding the bodgey foil, it is simply a wire link to bypass the missing batteries.

[attachment=751]