Cordless SCOPE charging current

Do that first and you'll find out whether the cells are dead, which is a fair possibility. If you have to replace them, you'll know what charger to use.

I'd be interested to know who you rang. I've lost track of who owns scope nowadays. My grandfather started the company in about 1950 but sold it in the seventies.

As far as I remember, they have an internal diode and limiting resistor and are designed to charge directly off a scope iron transformer (3.3 -

4V AC). I don't remember what the resistor is, but I think it was for a normal 14hr charge. I think you can fast charge them to about 70% capacity fairly safely.

There's nothing special about the batteries inside though. Replace em with nice new high capacity ones if you like. NiCd are best for very high current discharge, I believe.

hope this helps, pie

"Dave"

** On the side of the handle - Scope refer to 3 chargers, a 240 volt powered one, a 12 volt car adaptor and a 4 volt AC source (ie standard Scope tranny). ** The Ni-Cds are 4 amp hour.

Any Ni-Cd can take a 1 hour charge if you SWITCH OFF before they get hot - ie use a timer switch.

** Very lucky - I was given an old but never used Scope 60 Cordless and found the cells inside to be useless. ** Try that and see how long it takes the cells to get a little warm.

I replaced the cells in mine with Sanyo N4000R "fast charge " cells - rated for up to 6 amp charging.

Still only gives a 5 to 10 minutes of soldering.

Butane powered soldering irons piss all over it for portable use.

....... Phil

Thanks Phil,

Inside there is no limiting resistor as somebody suggested, but there is a piece of fuse wire instead, to provide a 'hard limit'! I was going to hook it straight up to my MiniScope transformer but since it can belt out about

30 amps or so it may not be the best idea without some sort of limiting resistor. Hooking it up to 12V would obviously be a no-no without dropping it first. The original owner had blown the fuse wire trying to charge it directly from his car battery, so I replaced it with a bit of wire, probably soon to be a current limiting resistor (I'd rather it overhead than blow if I'm on the road.)

You're right about it being crap for portable work. It's very unwieldly and completely the wrong shape and weight. Unfortunately the tip has had it on my old Portasol and I don't use it enough to justify a new $35 tip, but this cordless SCOPE was good value for $5 plus I can use the tips and accessories from the MiniScope.

Dave

No idea who I talked to Cory, but he just seemed to be a regular 'salesperson' - asking for the technical support section resulted in a confused 'uhhmmm...'

I charged it up overnight and it's heating up even better than yesterday, so the slow charge definitely worked. Not sure if it is worth me cycling the cells, somebody once suggested completely draining their cordless nicads every couple of months by dunking the tip in a bucket of water and putting a clamp on the 'hot' trigger. Sounds like a lot of work! Just so you maybe get an extra year or two out of some NICADS that cost $6-8 each.

BTW it doesn't seem to have a dropper resistor but has a piece of fuse wire which can burn out. This was burnt out on mine and I had no idea what to replace it with so I just used a piece of wire. Again, the guy on the phone had no idea what value it was, but could sell me a replacement bit!

Dave

"Dave G"

** Arrrrrggghh - DO NOT TOP POST !!!!!

** No fuse wire inside mine. ** No need.

The Scope tranny is rated for 3.3 volts AC under load - or about 4.6 volts peak.

The series diode loses about 1 volt when conducting 10 amp pulses PLUS some voltage loss in the cables making the voltage peaks on the two cells about

3.1. volts .

Close to ideal.

......... Phil

Nice! I'll just add a couple of screw terminals to the transformer and I won't need anything else! Couldn't be much easier.

Still can't find a dropper resistor in mine but I'm guessing it was removed by somebody who replaced it with a bit of fuse wire. Very odd.

Thanks again Phil! Dave

It might have been resistance wire. If it burnt out, it's likely someone tried to charge it off 12V directly. The 12V charger from Scope often had a light bulb in series to limit the current. Perhaps a 12V 5W globe? I forget.

Phil is right in saying a butane powered iron is heaps better. The Scope cordless iron is ok for a few odd jobs though.

cheers, cory

...

If you don't know how full they are how do you set the timer? do you mean use a charger with a heat sensor?

Bye. Jasen