Insomniacs Bedside Radio: signal to noise ratio

Raspberry Pi audio projects can be prone to noise issues.

I don't use our bedside radio very often, but when I do, I notice background noise.

I've finally got around to doing something about it.

Bluetooth Audio Transmitter Repair

We recently had a problem with our Insomniacs Bedside Radio.

The Bluetooth pairing button seemed to have shifted position within the box, causing it to be jammed on.

So time to open it up and reposition it, or so I thought.

Putting Radio Caroline back on 199 metres

Having refurbished our Bush VHF 54 valve wireless to a point where it is now a working radio, I have discovered that the Medium Wave band is a bit of an electromagnetic desert.

The strongest station in our area is something called Talk Sport, which mostly features two guys talking utter cobblers.

So if this old wireless is going to be more than just a piece of furniture, I need to establish my own radio station.

Bush VHF 54 refurb: some new valves

A few spare parts arrived this week, so I made some progress with refurbishing this wireless.

Its now a working set, although there is a lack of sensitivity on all wavebands.

However, I can tune in stations on all three wavebands and the tuning scale is now nicely illuminated.

Bush VHF 54: thermionic valve primer

The next step in refurbishing my Bush VHF 54 wireless is to have a sniff around the valves.

I guess that anyone starting a career in electronics after about 1970 has never had to study (or work with) valves.

So here is a quick and simple primer.

Bush VHF54: rewiring

Some of the rubber coated wiring in our family wireless was so badly perished that it just snapped and dropped off the wire when moved.

There was a real danger that one of these bare wires would come into contact with one of its naked neighbours, possibly causing damage to the set.

Therefore I just had to remove and rewire the main wiring loom to make our wireless safe.

Bush VHF54: replacing the drive cord

After being on my to-do list for the last 4 years, I've finally started work on my vintage family wireless.

This 1950s valve wireless was still working at the end of 2013, although the tuning mechanism had failed.

I bought 2 metres of cord from and eBay supplier, and set about getting it running.

The Insomniacs Bedside Radio

If you ever have difficulty getting [back] to sleep, you may find that reading a book or listening to music for a while will make you sleepy.

That's OK if you sleep alone, but turning on a light to read a book or cranking up the volume on your MP3 player at 2am may make you very unpopular if you share your bed.

But maybe you can get away with listening via a pair of headphones, if you keep the volume turned down low on your radio.

Raspberry Pi Software Defined Radio

OK, so I failed in my attempt to get the GQRX Software Defined Radio (SDR) to work on my Raspberry Pi.

But I've now come up with a simpler arrangement using rtl_fm that does work.

By using rtl_fm and some simple lines of code, I now have a Pi SDR with preset stations and the ability to fine tune.

SDR: Software Defined Radio

Having read a couple of articles on SDR (Software Defined Radio) I seem to have accidentally clicked the "Add to Basket" button, and ending up with some cheap hardware.

The required software is even cheaper than cheap. Its free!

So instead of doing important stuff like fixing the car or protecting our blue tits from sparrowhawks, I've allowed myself to be distracted.