Eagle International RP330N power supply.

Is it a "lab" power supply or just a simple regulated type?

Eagle International were not a manufacturer, they badge engineered other peoples product. Mostly they did not even bother to change the model numbers so it is quite likely that your PSU was originally a model RP330N.

It would be worth posting a picture in case someone recognises it under another name.

Study any PCBs for clues to the manufacturer.

Al

I don't think it's really a 'lab' type power supply. I've replaced the two vented caps and after a bit of digging I think the O/C transistor is a 2SD1021. I've replaced it with a BC639 (taking care of lead-out arrangements). Switching on produces a red light on the front (which happened before) No output volts and a new cap getting warm...... It's not overvolts causing distress to the cap, it appears the voltage to it is reversed. Caps in the right way of course (according to the PCB and the old one that came out). So no further forward yet.

Here are some pictures taken with it on my unusually tidy desk at work.....

Judging by the logo it's late 70s/early 80s. In the 1979 price list I have there is reference to an RP230N, but that's it...

Those white chip sockets look like the kind that go intermittent.
Give them a waggle and see if you get anything.

A liberal dose of Servisol Super 10 on the IC sockets and a multimeter across the cap that's getting warm would be my first suggestions.

Don't leave it on if it's getting hot, hot = Pressure, Pressure = exploding caps.

Dave.

Management have bought a shiny new power supply today so repair of the old one is probably not worth it now. I don't like throwing things out so may persevere a little longer. Apparently it's an old legacy item anyway from the days before the company was taken over so no loss if it ends up in the skip. It'll be useful for the 2N3055's and transformer if nothing else.

I would offer it FOC as there is likely to be someone down your way whom would be prepared to fix it.

Here's another Eagle power supply unit, the model RP230N. Can't remember when it was bought but the component date codes suggest late 1979 or early '80s.  The series regulator transistor is a Motorola 2N3055. Before any attempt to do a repair to the instrument that missing IC will have to be identified.    The eight pin IC is a Texas SN72709.

Till Eulenspiegel.

@till

This could be interesting! - I remember, at about that same time, building a kit of some sort which used those IC sockets, and hadn't really considered that just because the socket had say, 16 'pins' they weren't all used, so I complained to the company who supplied the kit (Doram Electronics) that they'd included an incorrect component. They wrote back to point out that I'd made the mistake, not them - egg on face moment, or what.

I'm guessing that you don't have the schematic for this? Could be an interesting exercise in logic and deduction.

Hang on, isn't the original subject of this thread a virtually identical PSU? That shows a 14-pin device in the lower socket.

Posted by: @cathovisor

Hang on, isn't the original subject of this thread a virtually identical PSU? That shows a 14-pin device in the lower socket.

Eyup! It does, doesn't it?!

Can't remember if the missing chip was an eight pin or fourteen pin device. The Eagle instrument proved to be unreliable in use and was replaced by the Philips power supplier you see in the Ever-Ready transistor TV set restoration topic.

Still, it might be worthwhile keeping faith with the RP230 power supplier. 0 - 30 volts 1 amp max current. It'll be fine for transistor radio repairs. I'm sure the instruction book still exists somewhere in the shop.

Till Eulenspiegel.

Posted by: @sideband

I've had a quick scan around the net and can't seem to find anything about this at all. In fact I can't find anything about Eagle International regarding the electronic stuff that was around in the 70's.

Gerry Adler's outfit wasn't it? He made a big thing about being able to speak Japanese and so negotiate with his suppliers directly.

http://www.richardsradios.co.uk/test.html

"History
During the 1960s and 70s, Eagle International were distributors of Eagle Products which included audio, amateur radio and test equipment which were mainly made in Japan. Their products were sold to dealers who then sold to the public. I understand that Eagle sold meters made for them by KEW. Gerry Adler who was the managing director of Eagle International previously had a business in the 1950s called Relda in Tottenham Court Road, London W1 which like many others sold radio and audio components and equipment. The Head Office was at Eagle International Precision Centre, Heather Park Drive, Wembley, Middlesex."

Possibly another SN72709, one as current comparator, the other voltage comparator?

Otherwise, there's a 14-pin DIL Toshiba variable voltage/current regulator IC, the TA7089, probably more likely to be fitted in a piece of Japanese kit than that 14-pin stalwart the uA723. Very much similar to the 723 but with a 3V rather than 7V reference, there's also a Signetics 14-pin 723-alike whose designation I forget, this time with a 1.2V reference- I'm sure I had a couple around but they're eluding me. I don't like PSU ICs in cheap sockets, I prefer them to be soldered in or at least in a decent turned-pin socket. It's very cheap insurance in something as fundamental as a bench PSU that might get used to try something expensive/unique!

That potentially looks quite a handy, if humble, PSU, at least it has separate meters as quite often analogue-metered units have a single meter and V/I switch which can be irritating. Worth a bit of time to sort IMHO.

That was my thought too at first, but if you look at the PSU that started the thread there's a 14-pin device in the lower socket. Okay, the model number's different but I'd have a quiet shilling on the difference being solely the output current. Perhaps @sideband could have a look in his (if he still has it) and enlighten us?

It is good to see separate voltage and current metering; the compact Farnell PSU (L30?) I have switches the meter which is a bit rubbish IMO.

My memory's been jogged as to how some op-amps were available in both 8-pin and 14-pin packaging in the early days, including ISTR the good ol' 741, with 14-pin variants having 2 pins at one end and 4 pins at the other end left vacant. Goodness knows why, it seems wasteful, but perhaps there was an intent to establish 14-pin as a standard somehow. Maybe something to do with big wire-wrap panels and robot wrap. (Not rap....)  Anyway, a look at the other side of the PCB would clear that one up quickly.

@turretslug

I thought I'd written that myself up-thread, but evidently I didn't. Yes, you could get 14-pin 741s and I suspect, other early op-amps.

The most recent example I can think of where pin-compatibility was considered was the TDA4500/4510/4555 colour decoder chips.

I have just found this site! Was in the TV & etc repair trade for 50 years!

I have an Eagle RP230N PSU which I have been modifying to fit digital V & A meters

Even better still - I have the the user manual which includes a cct description and dgrm.

It seems very similar to the RP330N.

If anyone is interested I can post the details on here.