Subchannel Stations: The Radio Broadcasts You Didn’t Know Were There

A good article on subchannel transmissions. Courtesy of Hackaday.

Analog radio broadcasts are pretty simple, right? Tune into a given frequency on the AM or FM bands, and what you hear is what you get. Or at least, …

Subchannel Stations: The Radio Broadcasts You Didn’t Know Were There

Sony ICF-480L 3 band radio assessment and repair

I originally posted regarding the purchase of this item in this blog post Sony ICF-480L 3 band radio

The radio was received earlier today. Cosmetically it is a bit tatty, batteries were placed into it and apart from a quick flash from the power light when it was switched on there was no sign of life. So the original description was false as it stated that it powered up with a very low volume. Oh well, not to worry, it now gives us something else to look at.

Tatty appearance

Looking in the battery compartment there looks to be corrosion, this seems to be a common problem with items I’m buying at the moment. The screws have all been tampered with so I suspect others have been inside this radio prior to my purchase, this could be interesting to see what’s already been tampered with or attempted.

I’ve had the unit open and the first thing that comes to light is the utter filth inside. The speaker is thick with god knows what and the board and switches are also covered in the same filth. Before I do anything I’m going to get this cleaned up.

I’ve used IPA on the board and cover and on the (thankfully small) corrosion on the positive battery pole and this has cleaned up nice. I’ve used contact cleaner on all the switches and dials and these have also come up ok.

The speaker grill, I have tidied up and used permanent marker to get rid of the marks on this item. This has tidied it up really nicely.

On the speaker I just used a dry cotton bud to wipe it over but I have my suspicions with this speaker, it looks quite worn and earlier reports on the lack and consistency of sound points to this being a potential issue with this unit. There are no clicks and pops when turning the unit on, there is a power and tuning light. Just no sound.

The speaker is a 4 ohm 1w speaker, I’ve used a multimeter to check its operation and it’s showing as dead, not registering at all, it should be looking at indicating something within its 4 ohm range. I’ve double checked it by putting a battery across the terminals and there are no pops or clicks so this confirms things. I now need to source a new speaker.

Trying to source this speaker in the uk is a tad problematic. There are items available but I’m not paying out two to three times the value of the whole unit. I’m going to try some thrift shops to see if there are any suitable donor units available if not I’ll have to purchase a few of them from China, and that will still be cheaper than purchasing here in the UK, crazy isn’t it? But it’s a long wait….

I did manage to get one from the Uk. Paid about £5.18GBP and it should be here in a couple of days. The annoying thing is that the postage is almost the same cost as the actual speaker and that only cost £2.69GBP. Annoying though that is, it has to be done if we want to get this fixed.

I couldn’t get a 1w 4 ohm speaker only a 1w 8 ohm speaker, this will be fine as at this level of use it will not affect output at all.

A small bit of desoldering, removal of the speaker clamp and the speaker comes away after a little persuasion. I take the opportunity to clean the board and all the battery contacts with some cleaner, and all corrosion marks and debris are now a thing of the past.

Corrosion cleaned

I put some contact adhesive on the speaker grill and put the new speaker in place, clamp is attached and I now solder the speaker wires back in place.

All screws back in place, new batteries in the rear and battery hat hatch closed, the unit looks good.

But does it work?

Radio works – have a listen

You betcha! Have a listen to the short video above to hear it as it should be.

I’m very pleased with this little project. Simple repair in the end but in my eyes it’s another item that isn’t going to landfill. And that’s a win for me, as it’s a nice little radio and I’m going to get some good use out of this.

Jobs a good ‘un 👍

Sony ICF-480L 3 band radio

I’ve purchased the item below from EBay. Got a bit of a discount and ended up paying £7:18 GBP in total. I need a small radio for listening to the sports commentary at work and thought this would be a simple enough project for me.

Sony ICF-480L 3 Band Receiver FM MW LW Portable Radio FAULTY Sold as SPARES

The unit is FAULTY. It powers on but the sound quality is poor and the volume is NOT loud. There is NO mains adaptor included. Sold as SPARES.

EBay

Cosmetically it looks a little tatty but a good clean up and touch up with a Sharpie pen might see to that, maybe a new potentiometer or just some contact cleaner might sort the sound issue out.

Sony ICF-480L

Anyway I will await delivery and post an update of the condition and repairs I will need to carry out shortly. You can see the assessment and repair of this radio here: Sony ICF-480L 3 band radio assessment and repair

I’ve got a bit of a queue of repairs on cameras still to come as I’m awaiting parts / components for them. So keep an eye out for a flood of updates on previous posts over the coming weeks.

Thanks for dropping by. Always appreciated.