Ear audio switcher for 48k+

[83dons]

Hi I am getting back into retro gaming after 30 years away and have a working ZX Spectrum 48k+. Currently I can load games using the old method of tape player with ear and mic wires plugged in to both. However to hear the volume better I have a 3.5mm headphone jack plugged into Ear and the red and white jacks plugged into my TV. This allows the TV volume to drown out the volume from the inbuilt speaker (not messing about with the wiring inside to cut the volume to the internal speaker!). However this means every time I play a game I have to swap the Ear jack in and out and I am not keen to keep doing this and damage the port.

I was looking for some sort of switch device whereby I could plug in one wire to Ear on the 48k+ and both the wires from the tape deck and the TV and switch between the two as required. This would mean that the Ear wire never needs removed from the port on the 48k+. I have switch attached to the power port on the 48k+ which means I don't need to keep pulling the power wire out of the device and potentially damage the port.

This sounds to me like a simple bit of electronics but I cant find a solution anywhere on eBay etc. Not entirely sure what to even search under! The power one was fairly easy to find. Does anyone know if such a thing exists and provide a link perhaps?

[1024MAK]

Back in the 1980s, there were various "LOAD" assist devices, some of which had a separate output for an audio amplifier.

I'm not aware of any modern devices, but then again, I've not gone looking for any.

If you can solder, you could make a switched unit.

The alternative is to buy an extension lead or a wear-saver lead. Then it's that that you disconnect/reconnect. The plug in the computer no longer needs to be disturbed and can be left in place.

One other thing. If you are not saving to tape, you could take the audio output from the Mic socket.

I've approved your post. Maybe other members have some other suggestions.

Mark

[83dons]

Back in the 1980s, there were various "LOAD" assist devices, some of which had a separate output for an audio amplifier.

I'm not aware of any modern devices, but then again, I've not gone looking for any.

If you can solder, you could make a switched unit.

The alternative is to buy an extension lead or a wear-saver lead. Then it's that that you disconnect/reconnect. The plug in the computer no longer needs to be disturbed and can be left in place.

One other thing. If you are not saving to tape, you could take the audio output from the Mic socket.

I've approved your post. Maybe other members have some other suggestions.

Mark

Hi Mark

Thanks for replying so quickly.

I guess its the nice switch unit I would be looking for but it sounds like no one has ever produced one as such. I don't have the skills to build one.

Your idea regarding wear saver lead is a good one as I'm mainly worried about damaging the port on the 48k+. Do you know where I would get the correct wire for this with port on it? That would be an ok solution for now and I can just swap the Ear wire and TV wire each time.

Ah so you could keep the TV sound wire plugged in and the tape should load from just the Mic to Mic connection should it? My other post in the forum details my slight confusion as to the ideal setup for using the tape recorder!

[1024MAK]

On the ZX Spectrum Ear is an input (*) and Mic is an output.

(*) However, you can pick up the output audio on both.

But LOADing is very unlikely to work if you are trying to use the Mic socket. See the other topic for more details.

Mark

[83dons]

On the ZX Spectrum Ear is an input (*) and Mic is an output.

(*) However, you can pick up the output audio on both.

But LOADing is very unlikely to work if you are trying to use the Mic socket. See the other topic for more details.

Mark

Thanks do you have an example of a wear saver lead that would work here? That sounds to be best solution here for now.

So if Ear is an input to the spectrum why does my TV use it as an output of sound from the computer to the TV (red and white audio)?

[1024MAK]

The designers of the ZX Spectrum used a single pin in the ULA chip to provide the tape input, tape output and the sound signal going to the internal "loudspeaker". Hence the Ear and Mic sockets are electronically linked. Both will provide an audio output. But, at different signal levels due to them having a different network of resistors and capacitors.

This network of resistors and capacitors is designed to give the correct audio level output for the Mic (for microphone) input on 'shoebox' mono cassette tape recorders that were commonly available in the 1980s.

Meanwhile, the network of resistors and capacitors connected to the Ear socket is designed to accept the audio from the tape deck.

Mark

[Lardo Boffin]

You could try something like this as a wear cable:

https://amzn.eu/d/0e3xey0a

Although probably a bit shorter one!

[83dons]

Would this be ok?

https://amzn.eu/d/06D9W9Gt

[1024MAK]

Yes, a "3.5mm Mono Jack Plug to 3.5mm Socket Extension Cable" is exactly what you want.

Mark