Hi everyone picked this up this week and plugged it in but no power at all were should I start looking maybe transformer? would anyone have a wiring diagram for one thanks

The first mistake was plugging it in. Considerable damage may result doing that.

It is highly likely that the electrolytics are finished & if it has paper caps they also will need to go.

Most of these old sets were shelved when they failed.

It always pays to slip the chassis of an "Unknown" set & inspect it to see if it is safe to actually plug in / power up.

I have had scores of sets where, on inspection, I have not even bothered or contemplated plugging them in.

It is amazing what you find inside. The Seyon 2D, that I posted for information on, actually had it's original (warranty expired 1927) "C" battery in it (Flat 2.3V not 4.5V). Grid leak was also open.

That was fixed before any power was applied: It ran, no further repair action required.

Marc

Here is a good place to start when working out the order things should be done in when acquiring a new set.

I'll admit right now that back in my early days of collecting I used to fire her up to see if she'd work when bringing another radio home from a junk shop or where-ever. Most often the radio would work though once or twice I'd get one that would cook its filter condensers on start-up. I even remember listening to a newly acquired Kriesler pump pudding one night to put me to sleep and it nearly did - too well. As I slept the volume went down and the temperature went up. I am lucky I am a light sleeper because I woke to the stench of transformer wax undergoing a physical change.

The batting average was a bit better in the 1980's and early 1990's when radios weren't as old as they are now. When I first started collecting in the latter half of 1988 the only really collectable radios were the 1920's coffins. Even radios from the 1930's that are regarded as classics now and fetch the best prices just sat on shelves.

Over the last 20 years or so the coloured Bakelite mantels of the 30's and 40's have become the most collectable in terms of investment value and because these radios are now 20 years older the chances that condensers and in some case power transformers remain in serviceable condition is getting far less frequent.

One growth area in vintage radio spare parts supply from here on, that I can think of, is the rewinding of power transformers and I hope to one day offer this service as the equipment to do it is easy to make from old bits and pieces.

In reply to your question about the Philips set, places to check are - condition of power cord - condition of power switch (if fitted) - visual check of transformer - check continuity and earth leakage of primary and secondary transformer windings with ohm meter or megger (if you have one) - check the age of electrolytic and mud caps (replace these as a matter of course, one by one as even if they still work they soon won't - check circuit for shorts - check tuning condenser for shorts - remove all valves, power up receiver and check secondary output voltages - if voltages are within specs power down receiver, insert rectifier valve and power receiver up again and check both the high tension AC output from the transformer and the DC output from the rectifier valve and make sure these voltages are within spec. Of course, you would have replaced the large condensers by this stage.

Brad,

I agree with the procedure for initially checking that set, for that a circuit will not be required at this point.

Perhaps we need to consider a specific / revised topic on Starting up the new aquisitions. I say this from the point of View that I repaired several hundred Valve radio's and have seen some Lethal examples.

Battery sets are not imune from nasty faults & meddlers, the efforts of whom have done considerable damage over and above any pre existing fault.

One of the best ones under the heading "You've got to be crazy" was a set that had been powered up "to see if it went". The mains cable was tatty cloth rubber and consisted, on all 3 wires of a series of 3/16" beads from plug to termination.

It still beggars belief that it did not go bang or kill someone.

Marc

The beads would serve a purpose in an industrial situation though imagine stepping on such a lead!?! Instant sore foot and minus a fair bit of skin.

As an electrician I've had a few belts in my time and it hurts sufficiently enough to wonder what someone would go through when they aren't able to let go. Then there is the high tension inside a set - where RCDs are completely ineffective.

Whilst I've never come across beads or similar items used as insulation I've acquired numerous radios over time with VIR figure-8 cable that has perished to the point where there is more wire than insulation. Single insulated flexible cords have been illegal on new appliances for a short while now - it only took 100 years.

Good idea about a general article on safety with new acquistions. I might bang something together over the weekend. I wish I still had the plum pudding I mentioned earlier. It'd make a fantastic illustration as to why looking before leaping is the best approach. As I didn't have the resources to repair that set at the time I ended up wrecking it for parts.

Hi Bling,

I have the schematic for a 178A if that is of any use to you.

Unhide your email address in you profile page and I'll send it on to you.


Cheers, Graham...

Brad,

Beads: Was not exactly made clear.by me.

The beads were the rubber insulation on the wire. It had dried cracked & was crumbling. This is why I could not understand the shear lunacy of plugging it in.

Marc

Hi graham my email is un hiden if not its blingbling81hotmail.com thanks again

Sorry Marc. I thought they may have been bare porcellain ones, typically used in places where there is lots of heat and where flexibility is required.

Still working on an article for newly acquired radios. Should have something up by the end of the week.

Marcc: The beads were the rubber insulation on the wire.

My Airzone is on the bench at the moment and I'm looking at what may become a similar sight under the chassis.

A previous owner has re-capped it -- except for one that has a choke wound around it and which I suspect is now a dud, but he left the rubber insulated point to point wiring as is. He did put a 3-pin cable and plug on it and earthed the chassis.

Given that there are no apparent shorts I'm debating with myself whether to leave well enough alone or roll up my sleeves and rewire it, too.

I've been quite lucky with the Astor. Good storage conditions, I'd say. Despite being nearly 50, all the electrolytics came good, and only two of the 22 paper caps have failed. Well, so far! Anyway, I'm of the "don't fix it if it ain't bust" school.

I'm of the "don't fix it if it ain't bust" school.

Generally, so am I but I am also concerned about the potential for fire with these old radios (I never leave them on when I'm outside).

I'm thinking of perhaps lifting one end of the old rubber wires and putting spaghetti over them. It might not be beautiful but it will be safer than the prospect of bare wires eventually shorting on something.

Then again, I might just bite the bullet and rewire.

I'll only get rid of VIR (rubber insulation) if it looks like it is breaking down or it has dried out. One exception is the power cord. I always try to replace these with cords from discarded irons if it is a coloured set as the synthetic cotton covering looks authentic enough. Otherwise I will use brown cotton covered flex supplied by Steve Savell - I bought a 100 metre roll off him a while back.

For the wiring under the chassis there's a couple of enemies.

1. Heat - if a component has overheated at some stage it'll cause VIR insulation to break down or simply melt completely.
2. Age - Manufacturing tolerances mean that rubber lasts a short time or a long time. Sometimes it just doesn't work out with rubber and it will age a lot quicker and break down.

I do a visual inspection. If there's no scorch marks around the wiring, no short circuits and the rubber has retained its original colour then I am happy to leave it as is. Short rolls of single core automotive wire from Jaycar will serve as a good replacement conductor.

It's worth noting that VIR cabling that used to be used in the hard wiring of buildings has a bad reputation however the only places it ever succumbed to the elements was at termination points. The rest of the cabling was always in split-seam conduit and when it is extracted during a re-wire job it's always been in good nick, as if it was installed the day before.

Hello from townsville.4 inch by 3 and a half souair. the transformer is big ,butt its out of a sine wave generator, techtron, melbourne -australia.tyoe [601ar] serial[230].d c a ident.no.y10/71.the transformer is like this [0] [30] [230] [240] [250] and [5volts for 2 amps] and [230volt] and [230volt] and 6.3 volts for 4 amps] and [sh is earth] now can some one tell where in australia can I get this item rewind/rebuilt/restored like new again. I have looked all over the internet in australia. as I can not post my email or phone number this is going to be hard.?in australia you should beable to post your email at lest or a phone number. thankyou to all who can help.please.?