Ham radio battery box Mk II

[Jack Crow]

Hi all,
This is going to be very similar to the previous posting.

The major change is an up current improvement.
Going from a 4 amp battery to an 8 amp unit in the interior space of the ammo box.

Other changes from the 4 amp variant.

Went to the local Harbor Freight and picked up some basic measuring tools.
Inside and outside calipers and a good metric ruler.
With them I was able to take good measurements inside the HF plastic ammo box.
Things I could not measure with the caliper.
Used the measurements to insure the printed parts would fit in the ammo box.

Now the front and back 'buckets' are the same part, so two are required.
They also provide room for cables and accessories that would go with the battery.
The narrow side pockets can hold papers or business cards.
There is a hold down clamp to keep the battery from banging around if the box is inverted.

The battery it's self is held in the middle.
This makes it good ergonomics due to center weight distribution.

It's going with me to the RASON radio club meeting Monday night. Then to the client.

View from the top.
I wish I knew how to take better photos of multiplexed LED's in action.
7-16-2017 001.JPG

The inside of the battery box.
Two 'buckets' on each end plus a hold down bracket in the center.
All the hardware is 4-40 stainless hexcap screws with flat and lock washers.
7-16-2017 003.JPG

View from the bottom. Had to use a cut off wheel to take down the excess screw length.
7-16-2017 004.JPG

What the whole assembly looks like spread out.
Been thinking about adding a fuse or a circuit breaker to the unit.
Plenty of room.
7-16-2017 006.JPG

This is a detail on the inside bucket attach screws.
On printed plastic parts I find that using large flat washers to be an advantage.
7-16-2017 009.JPG

If the club members like this thing and want some, have a couple of changes in mind.

Designed a simple tool to insure I drill the meter panel into the same spot every time.
It straddles the area under the top cover handle and the edge.
So I get a center hole and a general outline where the hole saw will bite.
Right now I am lining up with a ruler and a scratch all, good enough for prototype but not for any kind of production parts.

Improve the center bracket and make the narrow side pockets smaller to better attach a top bracket.

Fusing the output for sure.

Perhaps pick up an inexpensive battery tender and make sure it fits inside the case.
Right now these are charged using my bench power supply, and that is a touch clunky to move around.

So that is the news.
Be well all.
Jack Crow
Virginia Beach VA.

[Mooselake]

Wall wart and a cheap constant voltage/current board off eBay?

I've used the couple dollar voltage only version on my 12Ah AGM battery for around a year, only problem is that it lets the smoke out if you connect an Astron in parallel when you forget to disconnect it first.

Kirk

[Jack Crow]

Kirk
As for the charger im going to visit the "Battery Store" soon, I recall a cheap tender that might fit inside the case.
Found out from the client that the HF tender is crap.
Just handed the item off to the client, he is real pleased with the way it came out.

Was able to get a 'family photo' this morning with all three units on the kitchen table.

On the subject of equipment failure, it is very hard to cram all that magic smoke back into the failed parts.

In other news....

Had a good scare today.

I have two of these HP 6253A PSUs.
One at work and one at home.

The work one started to get stupid today.
Not delivering current, poor regulation.
Just being an electronic dingus.

Got it home and found that the problem was this large filter cap, the kind with screw terminals worked it's way loose and was failing the filter tasking.

Quarter turn with the #2 bit and it's back in spec.

Old tools, what a wonder.
Could not do that with today's high tech Chinese wonder import made with third world recycled parts.
Something to be said for a 1968 Oldsmobile, it was a car I could wrench on and stand a good chance of fixing.

Same deal with these HP's.
Little more maintenance due to age (me too!) but it keeps on cranking the watts in a meaningful way.

Anyhow, stay out of trauma.
Jack Crow in Virginia Beach

[Jack Crow]

Hi all
Some follow up photos.

Family photo of the first three battery box units.
The one with the semi clear meter panel was #1 with the 4 amp gel cell.
The other two hold 7 amp gel cells.
7-21-2017 001.JPG

The inside views.
7-21-2017 004.JPG

Keep it safe
Jack Crow aka Radio Mike in Virginia Beach