Help for newbie with HMV that doesn't turn on
 

Dear All,

I inherited an HMV record / stereo system from the 1950s. I've attached photos.

My grandmother said that it worked when she used to turn on it sometimes in the early 2000s. However it went unused for a decade. I plugged it in and turned it on but absolutely nothing happened. Left it on for 20-30 minutes and nothing started or kicked in.

I don't really know where to go or how to get the electrical issue resolved. I like to think that it's something simple like a switch. I'm not bad with electrics and audio equipment generally, but I've never seen something like this internally (photos attached).

Any ideas on what I should do to try and diagnose the issue or what sort of electrician could look into this?

All help appreciated. One radiogram restorer in Australia said he would not just fix one thing but do a full restoration and I really don't want that. Aside from the fact that it was horrifically expensive, the record player condition generally seems good given its age.

I thought it might be the switch (photos included) but that's a guess.

The system is an HMV N3-4Z

Best Regards

Re: Help for newbie with HMV that doesn't turn on
 

Get rid of those croc clips on the speaker to start with. I assume they're someone's crude attempt at adding an external speaker? If they both contact the speaker's frame they'll short-circuit the output stage and could cause damage.

As for the no switch on, simple continuity testing with a meter on ohms range will show whether power is likely to reach the turntable and amplifier. I'd suspect the OFF/ON switch, but I'm not one for replacing components because I think they might be faulty. I like to prove it.

Do you have a model number or name?

Re: Help for newbie with HMV that doesn't turn on
 

Details here.
Gaz.
https://www.radiomuseum.org/r/hismas...ric_n3_4z.html

Re: Help for newbie with HMV that doesn't turn on
 

Circuit here:-

https://www.radiomuseum.org/r/hismas...ice_n3_4y.html

Looks like there's a single pole mains switch and a socket which the deck plugs into.

Re: Help for newbie with HMV that doesn't turn on
 

The OP seems to have disappeared. I hope nothing bad has happened to him.

1950s HMV Radiogram won't turn on
 

Hi Everyone,

I am a first time poster and would say that I have a steady hand, good sense of logic and modern tech, but have virtually no knowledge or understanding of older electronics.

I do have a multimeter though.

My father gave me his 18th birthday present: an HMV Radiogram N3-4Z HMV.
Photos are attached.

You can unscrew the front panel which exposes its core electronics which I have included in photos. One photo is everything i see from the top and the other two are closer ups of the same.

I won't lie - I have a romantic vision of learning a little and fixing my issue, but perhaps this really needs an experienced professional.

Basic starting point: when I turn the switch on, nothing happens. It doesn't "turn on." My father was a bit surprised because 15 or so years ago (when last plugged in) it did work properly.

If anyone could give me a couple of starting things to check and how to check it, I would be much obliged. Happy to send more photos or give any info needed to assist. I will say I have a big curiosity about how it works, but happy to accept that it might all be beyond me!

Appreciate all help in advance.

Re: Help for newbie with HMV that doesn't turn on
 

Hello everyone - you had to forgive me. It appears I started looking into this in pandemic times and did a post, but lost track of it. Thankfully it's been linked up to my original post.
Thanks a lot for your replies! I had not even read them until this morning. Very very sorry, I think we got out of lockdown the first time around then and completely lost focus!

I have picked this back up and removed the crocodile clips and yes - looks like someone in the past piggy-backed external speakers. I found the other end of the wires tucked in some little part at the back. Not sure if that might have damaged something, but will continue on basis that we're dealing with another issue.

Just a little orientation if I can:

In the photo attached, I've numbered a couple of things.
1 = power cable.

May I ask if you can confirm what 2 to 5 are and whether this is something I would look to test with a multimeter if I'm trying to test from the start, bit by bit.

(As a side note, thank you for the referral to a schematic, but I wasn't able to open or download it so I could get a closer look).
Again all help appreciated.

Re: Help for newbie with HMV that doesn't turn on
 

The switch may have tarnished contacts. Sometimes it starts working if it is used repeatedly.

The internal moving parts may have failed or moved out of alignment.
I have repaired a few but it is a fiddly job.

If you connect one lead of your multimeter to the mains plug and the other to the soldered connections on the rear of the switch you should be able to check the continuity of the wiring (Live and neutral).

I sometimes solder a short wire link across the switch so that I can star to check the radio circuitry.

Most of us replace a few critical capacitors before applying power to valve circuits.
You may damage transformers if you don't.

Re: Help for newbie with HMV that doesn't turn on
 

If it hasn't been switched on for 15 years or more then I would strongly recommend you don't attempt it now without some checks.

Put it to one side and read as much as you can about the working of valves and radio circuits. This https://www.vintage-radio.com/repair...ion/index.html is a good place to start. It might seem daunting but it is basically fairly straightforward. Many questions you might pose have probably been answered already on this forum so use the search facility above to browse around the site. Having said that do ask questions here; everyone is friendly and take the view that the only daft question is the one you don't ask.

You will need to be able to solder so you need a soldering iron and some lead based solder (not lead free). Have a look on Youtube for soldering technique videos.

The professional repairer would charge a lot as repairs are time consuming and it is his living. With something quite elderly like this a repairer worth his salt wouldn't want to fix the most obvious fault, he would want to do a full overhaul as something else would probably go wrong meaning he would have to have it back and it might lead to the incorrect assumption that he hadn't done a proper job in the first place.

PS - There are high voltages around in valve sets. If you do decide to apply power and you don't get a flash and bang don't poke around with a mulitmeter until you know a lot more about what you are doing.

Re: Help for newbie with HMV that doesn't turn on
 

I would like to second Paul’s post.

As a professional repairer/restorer, I can tell you that restoring these types of radio/radiograms can be very time consuming, sometimes taking up to 20 hours! Though that’s quite unusual.

To answer your questions:

1. Mains cable
2. Mains transformer
3. Rectifiers (They convert AC to DC)
4. Valves, probably the output valves
5. Output transformer.

Does the turntable work when you switch it on? If yes then it exonerates the mains cable plug and on/off switch.

Please take great care, as has been said before, you need to check continuity of the mains cable, on/off switch and mains transformer and of course any fuses if fitted! (I haven’t looked at the circuits yet.

Re: Help for newbie with HMV that doesn't turn on
 

As already mentioned by Station X another way you can test the continuity of the power input is to switch your multimeter to the resistance setting. Put one probe on the live pin of the mains plug and the other on the output of the switch to the mains transformer with it switched on. You should get a very low ohms reading, if any resistance at all, on the meter. If both mains leads are connected to the switch then try touching the other output with your probe and look for a very low reading. Then move the probe on to the other pin of the plug and to the other output from the switch. I am excluding the earth pin of course.

If you put a probe on each pin of the mains plug you should get an ohms reading which is low, a few ohms. Again, I am excluding the earth pin.

All of this without it plugged in of course!

Re: Help for newbie with HMV that doesn't turn on
 

To add to the checklist for the the OP, do note that this is a Mono-only unit, so check if the original mono only cartridge is still fitted? If so, it will need changing if stereo records are to be played.

Re: Help for newbie with HMV that doesn't turn on
 

Thank you everyone for info.

You are correct indeed, I am reluctant to go digging around unless I effectively know what I'm doing. thank you for the references - I'll do some homework and research.

Yes - I do know how to using a soldering iron, and if this job requires that, I'm really going to have to know what I'm doing.

The main "on/off" switch at the front does not "click" like the other knobs do. It's more like turning a tap with a bit of resistance which made me wonder exactly how broken the switch might be and whether it accumulated dust and gunk over time...etc..

I'll do some reading, I might have to ask some silly questions here from time to time, though a great teacher once said to me: there's no such thing as a silly question....

And to Michael Maurice - no the record player does not work. I could swear that when I turned it on years ago, there "might" have been a light that went on behind the radio dial. But maybe I'm mistaken!

On the topic of record player, I have included a photo. Seems to have two switches - red and white ones, which are indicated by a green arrow.

Can someone give me a run down of what these do (in the spirit of "no such thing as a silly question") ?

Much appreciate the assistance
Matt

Re: Help for newbie with HMV that doesn't turn on
 

Actually it is a stereo unit I believe as it has two output transformers and two output valves.

Re: Help for newbie with HMV that doesn't turn on
 

The record deck is the very common Garrard Autoslim. The cartridge appears to have been changed at some stage.

Re: Help for newbie with HMV that doesn't turn on
 

It is a Garrard Autoslim - quite a well regarded turntable.

I have attached the manufacturer's instructions

It may well require a bit of an overhaul. Lots of information about that in the sticky threads.

The switch probably just needs a bit of lubrication - a squirt with switch cleaner - not WD40. The switch is often on the back of the volume control, usually black. Often there is a way in to squirt some lubricant where the terminals are. Not the time to apply power yet though.

If you can solder you are half way there!

Edit - I have just re read your post and see that the switch appears to be a separate unit. That should make it much easier to replace/repair. I have just successfully used silicone lubricant spray into something similar but I acknowledge that others on the forum do not approve of its use

Re: Help for newbie with HMV that doesn't turn on
 

I am attaching a copy of HMV's service manual for a N3-4y which seems very similar.

The main problems are with the capacitors that link the audio to the grids of the output valves (C23 and C24) and the smoothing capacitors (C28 and C30). The former hold back the HT voltage whilst letting the signal through. They are usually leaky, allowing a voltage onto the grids and upsetting the bias of the valves. This can lead to serious damage.

The latter are electrolytic capacitors which either become leaky or dry up. They may be ok and a good way to check would be build a lamp limiter https://www.vintage-radio.com/projec...p-limiter.html or you could simply replace them with similarly rated capacitors. A lamp limiter is, however a good way of applying power more safely (for the set not you!)

Re: Help for newbie with HMV that doesn't turn on
 

Yes, now i can see the circuit diagram you are quite correct. My apologies. Again now I can see it, the Garrard Autoslim looks to have been fitted with a stereo cartridge.

Re: Help for newbie with HMV that doesn't turn on
 

I have just been shocked by the price of new 6GW8 / ECL86 valves. You certainly wouldn't want to risk one for the price of a couple of capacitors!

Re: Help for newbie with HMV that doesn't turn on
 

hi Matt

you ask about those red and white buttons on the deck and someone kindly sent you the orginal instructions, but if you look closely where these buttons are you can probably see the settings embossed on the black plate near the buttons. The words/numbers were originally silver but after years of use they rub away but if you look closely you may still be able to see them

BTW I've never seen a N3 amp from a Caprice in that larger body before, very interesting. Judging by the deck I'd say it was 1962 or 63