Can Currah Microspeech be used with the Next?

[Sabreman64]

About 20 years ago I bought a Currah Microspeech (probably on fleabay). My memory was that the last time I tried using it (years and years ago) it was faulty. However, I remembered wrongly, as I tried connecting it up to one of my rubber-keyed Spectrums the other day, and it worked.

So, I'd like to try to get it working with my Next, if that's possible. The first problem is how do I enable the expansion bus on the Next? The SpecNext FAQ refers to a couple of pages in the Next manual, in the chapter on 'IN, OUT and Next Registers'. However, these pages don't actually provide instructions on how to enable the expansion bus. Not being an extreme Next nerd, I can't figure it out from the manual. So, how do I enable the expansion bus?

The second problem is how to get the sound to output through the TV. The Currah Microspeech uses UHF connections to make the sound output through a TV. But since UHF connections are no longer a thing, how can the sound from the Microspeech output through the TV when using a Next?

Could someone provide some help please?

[Seven.FFF]

It is often repeated that Currah uSpeech isn't compatible with any Spectrums that don't have RF output. Usually people mod them to output audio directly. Here's one such mod:

It is, apparently, possible to get it working without a mod. The audio is available on the 3.5mm mono input jack, albeit with with high output impedance, which means you need to run it into an amplifier.

[Seven.FFF]

Once modified (or not), here's a Next tutorial video from Tim Gilberts (of The Quill and PAW fame) including the Next OUT commands you need to type to enable the expansion bus and disable the internal hardware that clashes with the uSpeech:

[jamesh]

But if it works, it should be in the 48k mode only, am I right? I had one and it did not work at all when attached to a grey +2 (while working just fine with the original 48k). Also, manual for my unit did not mention any alternative ways of getting audio out, yet everything was working fine when hooking the audio lead to an amp without any hardware mods (again, with the original 48k). I think I still have it in a box somewhere, but I am afraid to connect it to the Next. Thanks a lot for confirming that it should be safe!

[Sabreman64]

Well, Robin, I've watched the first few minutes of that video by Tim Gilberts. Maybe I'm being a bit thick, but it wasn't really much help. First of all, it seems the Next OUT commands required to enable the expansion bus are different according to which peripheral you want to attach to your Next. That txt file on the screen had OUT commands for Interface 1, and different OUT commands for attaching a printer. So I don't know which OUT commands are required when connecting just the Microspeech to my Next.

Secondly, Tim mentioned attaching the Microspeech to a speaker. You mentioned attaching it to an amplifier. I don't have either a speaker or an amplifier. I think the only device I own that comes anywhere near to being a speaker or amplifier is a pair of speakers from an old desktop PC.

[Seven.FFF]

It’s been a couple of days since I watched it, but didn’t he say the OUTs were the same for the uSpeech and the IF1?

Basically the aim is to disable any internal hardware that uses the same port decoding, or has an its own ROM if your device also has its own ROM. This conflicting is a basic thing that all Spectrums suffer from, not a Next thing. Normally you would just be out of luck and would have to unplug the hardware that conflicted. On the next the hardware is all internal so you’re disabling it instead of unplugging it, but the principle is just the same. So it’s reasonable the OUTs to disable would be the same.

In this case, the divMMC (all divMMCs not just the one in the Next), the IF1 and the uSpeech all have their own ROM, so the solution is the same - disable the divMMC.

Sorry if you think Tim’s video isn’t good enough. You might only be the second or third person to even try to use a uSpeech on the Next in the last five years, so there aren’t hundreds of tutorials to pick from. If you can improve on it please do so, I’m sure the next person will appreciate it.

[Sabreman64]

No, I don't think I can improve on Tim's video - not at all. I just think that he could have explained what he was doing in simple terms for thickos like me.

In any case, as I said in my previous post, I don't think I have a speaker or amplifier suitable for connecting my Microspeech to. And as the audio lead from the Microspeech is so short, I think I also need an extension cable of some kind, and I'm doubtful I own one of those either.

[Seven.FFF]

PC desk speakers should be fine, and you should be able to get an extension cable from Amazon for a couple of quid. You probably want something with a stereo socket at the speaker end and a mono plug at the uSpeech end.