I agree with DD on capacitors for a few reasons. I've often thought that (and it wasn't known at the time they were developed) that it wasn't valves that should be considered consumables but the electrolytic capacitors and these rather than the valves should have been what was put in sockets. Probably about 50% of the radios I've restored electrically over the years have responded to a minimal effort including removing valves, replacing the power cord (this is automatic), basic electrical checks to make sure there's no shorts in the circuits or power transformer, check on the tuning capacitor, again to make sure it doesn't short out when turned and then, if possible, a check against the correct circuit diagram to make sure, as Member Marcc often says, that the radio hasn't been booby trapped by a monkey.

Short circuits and "monkeyed" radios can be serious electrical hazards and saving a few bob should never be used as a justification for not being thorough. I have never attempted reforming electrolytic capacitors because I don't see the value in it. I just replace them when they do not work or when they are decades old. And as a bloke that was once almost topped by a valve radio that decided to call it a day, I will never compromise on this or a few other matters relating to restoration.

On the other hand, with valves, if all valves are in a set and they can be cleaned, remarked with their type numbers, loose bases glued tight, even when more than 70 years old, they will all probably still be in working order and test at 80%+ on a valve checker.

All very well to say "don't try to reform the electros" except, in this case, it looks like they were replaced in the late 60s or early 70s, going by the style and colour.

In my experience with TVs, Ducon electros of this vintage are more likely than not still OK. UCC electros, probably not.

You can't get similar replacements and the under chassis space is already crammed.

It would do no harm at all to run them up on a dim bulb. That will tell you in a few minutes if they are OK.

If after that, the radio plays with no hum, you are ahead.

It pays not to be dogmatic about such things! They are not a safety issue.

Pragmatism wins out most times.

I am in my dotage, but learn something new each day. It is usually a simple issue, but has me asking myself all sorts of complicated questions.

Turned radio on, static still there. Radio off and checked the 6B8 and ECH 34. The connection between the metal cover and pin on 6B8 was 0.3 ohms, and looked very clean, so no problem there. The ECH 34 coating appeared to be well established where the glass meets the base, again no problem. Turned radio back on, and very little static. What the heck???? Suddenly realised I had turned off the shed lights, which are all LED type. Turned them back on, and static nearly ruined my eardrums.

Turned off lights, and picked up one AM station, which might be the only one in the local area (around Nowra, south coast NSW Australia). Some slight noise in the background, but acceptable.

Mickey will be going back to the owner in a few days (he lives in Tamworth) - I do this sort of stuff without charge, to help out old farts like myself.

Thanks again for all the wisdom from radio experts.

Wodbore (Rob)

Ah yes, the hash from modern devices strikes again.

My own work on this hobby was brought to an abrupt end when the authorities replaced my electricity meter with a digital one. The resulting noise destroyed all AM reception throughout the house and for 10m around it. Unlike lights, I can't turn it off.

Not sure what stations might exist in your area. I know the commercial station 2ST went to FM a while back. Maybe there's an ABC station still around.

Thank you for having the courage to admit to an oversight that many wouldn't admit to!
Did you know that the designed switching frequencies of those LED inverters actually fall in the AM broadcast band? 630kHz is a common frequency.

I live in a townhouse in Belrose. AM reception is only possible on radios with directional antennas and if you pick your spot and rotate critically to null out all the cackle.

For other radios, I ran a length of RG59 co-ax from the back room, along the side fence and 40 metres to a wire antenna installed along the back fence, where it's far enough away and high enough to get cackle-free reception. Grounded the shield to a length of copper pipe driven into the ground. Works a treat! I get noise-free reception on 630AM which is quite weak and vulnerable on the beaches.

On the top of the band you need to re-tune the antenna trimmer to get best sensitivity because of the capacitance of the cable. One day I'll experiment with a phantom powered amplifier on the back fence and some better cable matching to solve that wrinkle.

630kHz has lots of fizz at Wollongong also and this explains why. There is also monkey chatter interference at night from a northern Queensland ABC station on 630kHz. Fixed when newsradio went to FM in Wollongong.
Regarding your rear fence aerial Ian, how high did you have to go, as I am in the same position of having a rear fence (metal) at which I could instal a long-wire? There is bush behind this and the land is coal mine land with no nearby buildings, so should be relatively noise free.

Even that I am in a rural position, as noted several times, I am in no way immune from the RFI generating junk we get.

Decades ago it was just white noise from the RF riding on the mains, from the HV aerials. That, I filter out. CFL's I have phased out for noise and I have had noisy LED lights that were returned to place of purchase. One in particular computer is an RFI generator, However, its blown its PSU that has shut it up for the moment. I have had a FAX get into a175kHz IF.

The absolutely worst RFI emanates from the wireless broadband. Its like a symphony orchestra and has to be shut off to service an calibrate an AM radio.

So you are not alone with RFI. Most filters here are permanent on lines, as, aside from the RFI, there are lightening surges, which means that there are strategic Metal Oxide Varistors to deal with it; Built into those filters.

Yes, my rear fence backs onto Forest Way Belrose. It consists of concrete brick pillars interspersed with treated pine panels, surrounded by trees and shrubs. The wire was just run along the timber and around the pillars.

Surprisingly, the often-heavy traffic doesn't have much impact on the reception.

A metal fence would probably need the wire suspended on insulators. Mine would benefit from that no doubt but it works well enough as is.

Thanks for that Ian. Will cobble up an appropriate balun/aerial transformer and try this out.

As Yaesu 7700 radios die do keep an eye out for their antenna matchers. They actually work. For confined spaces never forget the loop antenna.

Ian, I'll be dogmatic on caps because I have had a few times when capacitors have either tried to overheat a transformer and terminate my existance or in the case of power factor correction units, have quite large capcitors blow up right next to me. I am happy for everyone to operate according to their previous experiences but I think it is a bit much to expect me not to.

If I happen by a radio and I suspect it has not been restored by others, I will systematically replace any and all electrolytic capacitors regardless of whether the radio is 30 years old or 130. If some think that is a step too far then so be it. I am happy to spend the few dollars it costs to install new ones and know for 100% certain that they are going to go the distance.

On an unrelated note, but for much the same reasons, I will never leave a valve radio running whilst I am not in the same room listening to it.