Valve Radio

Talk Electrician Forum

Help Support Talk Electrician Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

OnOff

Mad Inventor™
Supporting Member
Joined
Dec 25, 2011
Messages
5,468
Reaction score
78
I got given this today.....at least I think "Take it and see if you can get it going!" meant it's now mine. 'Tis a thing of beauty:

A genuine, vintage, Marconi valve radio:

20160723_182428.jpg

Wonder if I can get a manual for it?

20160723_182828.jpg

I used to, as a kid have a whole collection of them but my Mum insisted I get rid of them.

Needs a clean inside & out:

20160723_182609.jpg

It has Short Wave on up to around 26MHz:

20160723_182501.jpg

So what's "M" stand for? Please nobody say "Meutral"

20160723_182619.jpg

Plan is a long bit of conduit single wedged into the aerial socket and stretched up the garden. Would it work better with a ground rod too?

So tonight's plan is pour a beer and listen to the "wireless"!

 
Well, IT'S ALIVE!

Brings back memories, the smell etc. Though it was dead then realised it had to warm up!  :lol:

Modern plug top on the lead and all the valves are lit (I think). 

20' of single insulated strung out the back door and onto the trellis. 

Random music and voices though not a lot. MW dead i.e. just static. LW busiest and something on one of the SW bands.

Main problem is the front tuning knob is attached to the dual variable capacitor by a chord/string that's slipped off but by gentle encouragement with a long insulated driver I can get it to change frequency.

Just feels wrong to be drinking LAGER doing this. Guessing mild or stout would be more appropriate.

A ground rod does help but I think you may struggle to listen to The Archers.

You'll be OK if you can read Morse Code


.. .----. .-.. .-..  -.- . . .--.  - .-. -.-- .. -. --.

:lol:

 
Probably wants a good dose of contact cleaner on the waveband switch.  Re stringing the drive cord should be easy, I'll bet you can still get it on ebay, or probably even CPC

Watch the electrolytic capacitors on a set of that age, they have a habit of drying out and going bang in a spectacular way. One school of thought on something that hasn't been used for a while is bring them up to voltage slowly, that's what a variac is for.

I used to have lovely old sets like that, oh how I wish I had kept them.  I do have two more modern valve radios in bakerlite cases that still work.

Here's the service manual http://www.mauritron.com/Marconi-T14A-Service-Manual-download-Ref12068  Perhaps if you search harder you might find a free one.

 
Last edited by a moderator:
Last edited by a moderator:
Found this for nowt:

https://www.google.co.uk/url?sa=t&source=web&rct=j&url=http://doctsf.com/documents/schematheques/radio_anglais/MARCONI/T14A.PDF&ved=0ahUKEwjDyMyWr4zOAhVL7RQKHZRHBG4QFggbMAA&usg=AFQjCNH4qqXrnKP7PC7xrbBJKsw0YRGPAA

From memory didn't  they, in the old days just have a damn great long wire stretched up the garden? But then wasn't there a lot of action on LW?

Saying that would nominally 30' of wire be better than a really long wire for 10m reception? 
its all to do with SWR

 
I thought SWR was to do with reflected transmissions rather than reception.

Reception is down to antennae tuning so that the received waves turn the aerial into a resonator which then self amplifies the signal, passively.

 
I thought it was all to do with wavelength.....i.e. matching the antennae length to the frequency you're  monitoring. Vaguely remember  a bit of 15mm copper tube about 9' long with some "ground rods" being used for CB as a 1/4 wave?

 
I love old radios  wirelesses like that .      Short Wave should give you some of the amatuer radio guys  I'd think , perhaps taxis , aircraft. 

Long wave , I think you will only find Radio 4  ( The Home Service)  

Medium wave has various english language stations including Radio 5 .

I used to like to hear that oscilating noise as you searched for a station.

 
SWR will help with RX as in TV aerials, but you are correct its more the TX side that is more important to get right, as it saves the output transistors, by stopping them letting all their smoke out,

 
Come to think of it I've a box of CB radios in the loft somewhere. 

Back to the valve radio. Ref the earth terminal on the back, was it the norm just to run a bit of insulated wire to an earth rod? I've got everything to just "TT" it. Not sure on the aerial and earth socket size, circa 2mm maybe....obviously Imperial. The earth & antennae sockets are the two just above the "K" on the chassis, 3rd picture down.

 
Last edited by a moderator:
26MHz would be closer to 12m than 10 or 11m

If you have a McKinley in that box of CBs I'll have it for a fiver,

Running a superstar gold in van atm, too much on it I can't understand,

I remember as a kid getting CQ cards from south america running the McKinley on 12w ssb with a home made 1/4wave ally antenna in the loft,

 
26MHz would be closer to 12m than 10 or 11m

If you have a McKinley in that box of CBs I'll have it for a fiver,

Running a superstar gold in van atm, too much on it I can't understand,

I remember as a kid getting CQ cards from south america running the McKinley on 12w ssb with a home made 1/4wave ally antenna in the loft,
Nothing SSB. A Uniden and then the near exact Audioline version. A Harrier too I think. All UK40 27/81. One or two will have "10 below" I added back in the day. There's also a President Veep AM/FM US spec. I always fancied a Colt Excalibur or failing that a Ham International Jumbo.

 
my first in 1979 was a trident (747 I think )my last a Cobra 148 with a K tone, Silver Eagle, through a Silver rod on the soil pipe

 
Last edited by a moderator:
My first radio was an 1155B transceiver out of a Lancaster bomber.

My Dad bought it from a government surplus place in 1946.

He made up a dipole aerial and strung it in the garden.

For all his wise words about it when I was a child,

I never understood the attenuation and propagation side.

I was too busy listening to the American forces broadcasts for Europe. 

 
Top