Radios using the mains as an aerial. - UK Vintage Radio Repair and Restoration Discussion Forum

Radio_Dave · 18th Aug 2006, 1:10 pm

According the 'Trader Sheet' my Marconi 264 has a mains aerial

It's connected to the live side of the mains supply, via a 'mains aerial coupling capacitor'. The 'aerial' disapears, in the wiring loom, under the chassis and I can't find where it terminates?.

I've never heard of such a thing and I'm not sure what to do with the aforementioned cap (leave it, class X2, etc?).

Any advice?

Thanks
David

ppppenguin · 18th Aug 2006, 1:54 pm

Don't know the set but if you are using a cap in a position where failure could result in personal injury it should be a class Y. The usual example is from live to earth in a mains filter network where failure could leave accessible parts live. Otherwise class X is fine.

Radio_Dave · 18th Aug 2006, 2:42 pm

I've just found out what the 'mains aerial' is... it's a mains aerial!

.

The live side of the mains (via that capacitor) can be plugged into the external, aerial socket with a wander plug

Perhaps I should just disconnect it? But just out of interest would it work?

Thanks
David

Brian R Pateman · 18th Aug 2006, 3:31 pm

In all probability it would - after a fashion.

These days the mains supply carries much more HF interference due to switch mode power supplies and the like so it would probably be very noisy. There have been a number of threads on mains borne noise in the last few months.

Try it and see - after making sure that it is safe, the cautions advised in Jeffrey's post are wise indeed!

Regards,

DoctorWho · 18th Aug 2006, 6:25 pm

I have a number of these pre-war EMI sets with the mains aerial, it seemed very popular on sets with the Jubilee Chassis and similar mid 30's.

I have never yet found one of the original condensers to have failed (that's not to say you shouldn;t replace it for safety sake) and I have tried it out on all of them, whilst not as good as a proper aerial it does allow the reception of stronger signal pretty well.

Peter.

Dave Moll · 19th Aug 2006, 11:44 am

If I understand the above correctly, I assume that it is using the power supply lines as an aerial. If this is the case, it would presumably work best with overhead supplies. Unfortunately the power lines where I live went underground about three years ago.

DoctorWho · 19th Aug 2006, 1:17 pm

Yes that's right. Thankfully they are still overhead here and so receiption is good, the only downer here is that there are not so many MW stations on the air here as there are in other areas sadly.

Radio_Dave · 19th Aug 2006, 1:32 pm

Well, I'm sure that a 'normal', length of wire, aerial will work better and be alot safer, so I'll disconnect it from the mains but leave the cap and flying lead in place

.

Thanks
David

18th Aug 2006, 1:10 pm	#1
Radio_Dave Nonode Join Date: Jun 2004 Location: Norwich, Norfolk, UK. Posts: 2,543	Radios using the mains as an aerial. According the 'Trader Sheet' my Marconi 264 has a mains aerial It's connected to the live side of the mains supply, via a 'mains aerial coupling capacitor'. The 'aerial' disapears, in the wiring loom, under the chassis and I can't find where it terminates?. I've never heard of such a thing and I'm not sure what to do with the aforementioned cap (leave it, class X2, etc?). Any advice? Thanks David Last edited by Darren-UK; 15th Jul 2011 at 2:06 pm.

18th Aug 2006, 1:54 pm	#2
ppppenguin Retired Dormant Member Join Date: Dec 2003 Location: North London, UK. Posts: 6,168	Re: Marconi 264 mains aerial? Don't know the set but if you are using a cap in a position where failure could result in personal injury it should be a class Y. The usual example is from live to earth in a mains filter network where failure could leave accessible parts live. Otherwise class X is fine.

18th Aug 2006, 2:42 pm	#3
Radio_Dave Nonode Join Date: Jun 2004 Location: Norwich, Norfolk, UK. Posts: 2,543	Re: Marconi 264 mains aerial? I've just found out what the 'mains aerial' is... it's a mains aerial!. The live side of the mains (via that capacitor) can be plugged into the external, aerial socket with a wander plug Perhaps I should just disconnect it? But just out of interest would it work? Thanks David

18th Aug 2006, 3:31 pm	#4
Brian R Pateman Nonode Join Date: Jun 2005 Location: Western Lake District, Cumbria (CA20) - UK Posts: 2,136	Re: Marconi 264 mains aerial? In all probability it would - after a fashion. These days the mains supply carries much more HF interference due to switch mode power supplies and the like so it would probably be very noisy. There have been a number of threads on mains borne noise in the last few months. Try it and see - after making sure that it is safe, the cautions advised in Jeffrey's post are wise indeed! Regards, __________________ Brian

18th Aug 2006, 6:25 pm	#5
DoctorWho Rest in Peace Join Date: Apr 2005 Location: Devon Posts: 850	Re: Marconi 264 mains aerial? I have a number of these pre-war EMI sets with the mains aerial, it seemed very popular on sets with the Jubilee Chassis and similar mid 30's. I have never yet found one of the original condensers to have failed (that's not to say you shouldn;t replace it for safety sake) and I have tried it out on all of them, whilst not as good as a proper aerial it does allow the reception of stronger signal pretty well. Peter.

19th Aug 2006, 11:44 am	#6
Dave Moll Dekatron Join Date: Feb 2005 Location: West Cumbria (CA13), UK Posts: 6,130	Re: Marconi 264 mains aerial? If I understand the above correctly, I assume that it is using the power supply lines as an aerial. If this is the case, it would presumably work best with overhead supplies. Unfortunately the power lines where I live went underground about three years ago.

19th Aug 2006, 1:17 pm	#7
DoctorWho Rest in Peace Join Date: Apr 2005 Location: Devon Posts: 850	Re: Marconi 264 mains aerial? Yes that's right. Thankfully they are still overhead here and so receiption is good, the only downer here is that there are not so many MW stations on the air here as there are in other areas sadly.

19th Aug 2006, 1:32 pm	#8
Radio_Dave Nonode Join Date: Jun 2004 Location: Norwich, Norfolk, UK. Posts: 2,543	Re: Marconi 264 mains aerial? Well, I'm sure that a 'normal', length of wire, aerial will work better and be alot safer, so I'll disconnect it from the mains but leave the cap and flying lead in place. Thanks David