Time electronics current source model 505
 

I Picked this item up for a fiver as it looked a bit different and also I am not sure what it would have been used for.
From new it would have beet powered by nicad or nimh batteries but the twiddler has been in and added a PP3. This battery was well rotted but as it had laid in the base of the cabinet only the press studs were rotted and they are not original anyway. I can understand why the battery was so bad as the unit produces 100ma so more than a PP3 can provide.
It must have been used to check something that was too large to be carted away to a calibration lab.

Re: Time electronics current source model 505
 

I have a couple more photos.

Re: Time electronics current source model 505
 

Time Electronics are well-known in metrology circles, and are still going strong after nearly 50 years. Based down in Kent: http://www.timeelectronics.com/

I've got a small number of their products. In fact, I've recently done an article about the 1030 Micro Cal: http://www.markhennessy.co.uk/time_e...1030_microcal/ - I was really impressed with how helpful they were when it came to restoring one of mine.

That one is a combined voltage or current source, and can supply up to 100mA from a PP3 with no problem - just not for very long ;)

I also have a 404S, which is very similar to your 505, but a voltage source rather than a current source.

These sorts of things are incredibly useful to have around if you're doing R&D. Some people use them to check the calibration of their meters - a bit like those Chinese voltage references that we've been discussing in recent months - but to use them for just that is a waste of their capabilities.

If you're not sure what you'll use yours for, I'll give you £6 for it ;D

Re: Time electronics current source model 505
 

agreed, their calibrators like yours and the mV and resistance versions are well known in calibration circles. They were the way to do things before integrated digital computerised calibrators came about and are often found in factory labs and workshops. That one there for example might have been used to simulate a 4-20ma signal transmitter in some industrial instrument such as a pressure sensor or modulating valve motor.
Don't drop it, they're over a grand new

Re: Time electronics current source model 505
 

Another fan of Time Electronics here, I have a 2003S D.C Voltage Calibrator.
Here's a picture of me wasting it checking the calibration of a cheap Chinese meter.;D

Beware these things are infectious, I bought a Chinese voltage reference as a check and then a Solartron 7150plus, now I'm lusting after a Keithley 2015 THD or even an HP 34401A.

Jim

Re: Time electronics current source model 505
 

That a nice one! And if that LED module is the one I think it is, I bought a few of them a couple of years back (along with a few other types). I was pleasantly surprised at how accurate they all were for the money...

Re: Time electronics current source model 505
 

£1000 is quite a bit of money.
The twiddler has also drilled a hole and added an extra power cable that is connected across the PP3 battery. I have no idea why.
If you look at the second photo in my second post there is a charger connector so in its day there would have been no issue with it being able to provide 100ma.
I will keep it and add some expensive resistors to get voltage as well. It will then be good for checking volt meters too.
I forgot to paste the link to the website but never mind that soon got sorted:clap:
The PP3 mod has been added to the original Molex header with squeezed spade connectors so it is reversible.
It looks like I can get a 6 cell AAA holder in there and load it with NiMh cells.
Does anyone know the name of the charger connector?

Re: Time electronics current source model 505
 

I don't know the right name for it, but I think this is the plug that fits it (from RS) :

http://uk.rs-online.com/web/p/1-mm-t...ckets/0466472/

I think you have to order the cover seperately if you want to put it on a cable (rather than mount it on a panel.

Re: Time electronics current source model 505
 

Hi,
I used the 404/505 voltage and current Time units in industry for many years for field calibration checks but they were laterly supeceeded by microprocessor controlled units. There are various power options some used AA cells.

Typically uses were for injecting signals into a wide range of industrial transducers ,actuators and computer control systems to prove inputs and check responses. They can also be used for Low Ohm resistance measurment using a constant current and measuring the voltage. ( basic 4 wire kelvin method) The units also came in various acurracy varieties.

Here I have a microcal as described by mhennessy which gets all sorts of use from meter movement checks , transistor base driving tests and resistance checks as above.
Pete

Re: Time electronics current source model 505
 

That RS part looks right but before ordering I will need to measure up and compare with the data sheet. It will cost about the same as I paid the flea market trader for it just like a replacement valve in a radio.
The battery compartment only has enough space for 6 AAA cells so the original battery will have been something along those lines.
I like the idea for measuring low ohms. Perhaps I had better set about making an external box to plug into it.

Re: Time electronics current source model 505
 

The 404S uses 6AAs, in two of those tube-style holders - you can see them in this video: https://www.youtube.com/watch?v=ElJXTxu_TnM

From your pictures, it seems you have a different arrangement. I'm guessing that the module with the fuse, etc is some sort of power management unit that deals with charging batteries, etc, and I could imagine how the cells would fit there.

Time might be able to dig out a manual - drop them an email...

Re: Time electronics current source model 505
 

Yes indeed mine looks like it used to have a special battery with a 2 pin Molex plug like the plug on the left. There is a pair of bodged spade terminals pushed onto the Molex pins. It will be able to take 5 AA cells but perhaps 6 AAA cells will fit. The fixing holes for the special battery are too close together for AA cells to fit.

Re: Time electronics current source model 505
 

The original must have contained AAA cells.
I just need a battery holder and a 2 pin Molex connector.
As it will be only for occasional use I will leave the charger plug and go for charging with a regular charger.

Re: Time electronics current source model 505
 

I have this nifty little unit, made by Time Electronics picked up a a local boot sale, some years ago, I think I paid 50 pence for it ;D

And still accurate today.

Attachment 125121 Attachment 125122

Paul.

Re: Time electronics current source model 505
 

That is a nice compact one.
I just have to wait until next week and then I will go to Maplin and get a battery holder.

Re: Time electronics current source model 505
 

It's the one I linked to in post #3, where you'll find internal pictures and full schematics (that aren't available elsewhere). Cost me considerably more than 50 pence though ;D

I think the originals would have been a set of AAAs shrink-wrapped in a package, but like I said, drop TE an email - they might still have them, and they might not be all that expensive. Certainly, the bits they sent me were extremely reasonable.

I also have a 303 'scope calibrator here, and that has a similar deal, but the cells are larger than AAA - I think they're C types, but I haven't had a chance to properly investigate and restore it yet.

Re: Time electronics current source model 505
 

I reckon NOS batteries would be nothing but trouble. I will wait for the battery holders and then contact them for the 2 pin Molex connector and the charger plug.

Re: Time electronics current source model 505
 

Clearly I didn't mean NOS - I'm saying that from personal experience, I know that they support their products extremely well - even old ones - and so it's quite possible that they'd still have new battery packs in stock. Also, there is a newer version of the 505 that is also battery powered, so that gives options too.

I realise that you have a plan that sounds feasible, but if nothing else, I'm hopeful that anyone reading this in the future might decide to drop them an email rather than give up on (or modify) a viable bit of gear, just because it's old.

Contrast the support they gave me with Keithley: in response to my email, I got a "your email was deleted with being read" notification from them. As a result, the one bit of Keithley gear that I own will no-doubt remain the only one.

Re: Time electronics current source model 505
 

There is no need to do any modification.
The original battery was fixed in place with a steel bracket that is in my case missing.
I shall make a new bracket to carry 2X3 cell AAA holders and fit it in place of the missing bracket.
If a new bracket is found it is just a quick swap back to original.