Making Tape Great

Finally, I managed to get around to testing the cassette recorders with a working ZX Spectrum. (Note that all this playing was done with the minimum of repair work - there are separate posts coming on what I fixed (or didn't)...)

Unnecessary Spectrum Pic

But. I didn't have any mono cables. I tried a stereo one and found that it was, to be blunt, useless. A stereo jack has a connector made of three metal sections. The one at the tip that enters the socket first (no sniggering at the back) is left audio, the one in the middle is right audio and the sleeve at the bottom is ground. For 3.5mm mono the tip is audio and the sleeve is ground.

In all the cassette recorders I have the 'ear' sockets are constructed so that the mechanism that holds the plug in place makes contact with the tip and sleeve for ground as expected.  But the point at which the ground connection on the plug varies. As a result, the cassette recorder might make contact with the tip and ground sleeve but the Spectrum at the other end has contact with the tip and centre ring i.e. no direct connection.

To get around this I came up with a (bad) idea. Take an existing stereo jack to jack lead and join the sleeve and centre ring together at one end. I won't bore you with the details but it was a little bit successful and a lot not very good. It did work and resulted in my getting one of the cassette recorders to load my game but with an additional blob of solder on the plug I was concerned I would damage the sockets. So I abandoned that idea and ordered some cables from eBay. 

A fine example of what not to do..

That's better..

Now I have all the right equipment it's time to get going. Here's the setup I'll be using, a 48K issue 2 ZX Spectrum with a composite mod. The TV is a 6 inch Sony Trinitron kindly donated to me by one of my most excellent work colleagues. I shall be trying to load 'Flight Simulator' by Psion. It should take about four minutes and consists of a very small initial program load, followed by a loading screen and then the main program.

Watched over by Baby Yoda.

So, there are actually six machines that I have and I have listed the results of my shenanigans below:

Sanyo M787G

This one couldn't be tested. It's sadly not working. I do have the service manual for it and I am hopeful that I will be able to get it back up and running again. Watch this space.

Sanyo DR-101

This is the most modern of the recorders I have (if they can ever be called 'modern'). It's also the most slimline and the lightest.

Load that sucker!

Looks promising..

This unit has a switch on the side labelled 'Normal' and 'Data'. I started in the 'Data' position and it actually failed the first time. 

..spoke too soon.

This was a slightly disappointing start to say the least. I switched it to 'Normal' and tried again. Volume was at maximum and it still sounded very quiet through the Speccy speaker. But it worked.

Load time : 3 minutes 57 seconds

Philips D6310

This one was basically a big pile of plastic bits for a long time. Following the 'great reconstruction', thanks to the supply of new cogs from my awesome brother, it now works - or at least it plays cassettes. It's very noisy but it could just need some lubrication in the right places. Not so sure about whether it will load Speccy games.

It's a beast.

First attempt, well it didn't go well. It did get as far as the loading screen but the bottom third was the wrong colour and once it finished that block I was presented with the infamous 'R tape loading error' (again).

So close, but so far...

Second attempt, re-seat cable and reduce volume very slightly. And...even worse. It didn't even get to the screen before the tape loading error message made another appearance.

Our situation has not improved.

Load time : FAILED

Bush (no model number)

Note the 'Rank Organisation' Logo

I had high hopes for this one and I wasn't disappointed. Well, not as much as for the D6310. This one has a handy 'tone' control along with the volume and I set them as you can see in the picture, volume about 9 and tone about 8. 

I'll give it this, it loaded the game without any problem at all. The only fly in the ointment was the loud clanking from the mechanism as it played. I could remove it completely by gently applying pressure to the 'STOP' button so there is obviously something out of alignment inside. And the rewind refused to work too. Some work required on this one then. But at least it loaded!

Load time : 3 minutes 53 seconds

WH Smith CPD8300

A mighty machine

This is another beast and the only one that came with its own plug attached. It has a 'monitor' switch too so I could listen to the cassette output at a decent volume from the speaker. On the back is also a selector switch that could be either 'Spectrum' or 'Other'. What is it about the Spectrum?!

What else is there, except 'Spectrum'?

No problems loading with this one. The only thing is that the 'monitor' function could really do with a reduction in volume. I had to put my hand over the speaker, the bloody thing was so loud! I did try again with the monitor switch to 'off' and it worked fine too - and was much quieter.

I did have some problems with this one randomly stopping but I put that down to the tape being wound too tight (thanks to the Bush machine). A quick fast-forward and rewind sorted that out.

Load time : 4 minutes 9 seconds

York Radio Cassette

I hit an unexpected snag with this one. The audio out was a DIN socket and I couldn't find a headphone socket...

No 3.5mm socket? Sad face. :(

So, after all that, I only managed to get four machines of six machines actually tested and, of those, only three would actually load the game. The biggest disappointment to me was the Philips as I put many hours into getting the bag 'o bits back into something sensible. There are still some tweaks I can do it so all is not lost with that one.

I was very interested to see the difference in loading times. Over four minutes for the WH Smith unit just confirms what I thought in that it runs much slower than the others. 

Loading from tape is archaic and very, very slow and error prone. But those noises whisked me straight back to the front room of my Mum and Dad's house in 1984. Happy days. :)

The Most Challenging Composite Mod - In the WORLD. (Maybe not..)

A short interlude before I start playing with cassette recorders..

My Acorn electron is still waiting for some more attention, mostly because I don't have the correct cable to load cassettes and I don't have the 'retro' budget to splash out on the available SD card type options. 

An Electron walks into a bar...

But one thing I hadn't realised was that the composite output is actually monochrome. I was quite surprised at this as I knew I'd seen videos of people using their electrons with gloriously garish colour through composite. Well, it turns out a fact well known to Electron aficionados is that there is a very, very simple mod that can be made to change the monochrome output to colour. This was completely unknown to me, of course, but here's the proof, direct from the Electron service manual:

So, according to this, all I need to do is bridge the link labelled 'LK4' and it will add the chrominance component to the composite output i.e. monochrome becomes colour.

Time to break out the screwdrivers.

Electron bottom...

Gratuitous Action Shot

Under the hood.

With the motherboard completely removed from the case I just needed to find LK4. It wasn't too hard to find.

LK4, whereart thou?

Gotcha!

With the link located I decided to take a leaf out of Mark Fixes Stuff's book and, instead of just soldering a link across it I would add a couple of header pins to allow a jumper to take it back to monochrome i.e. it would be reversible.  After a bit of scrabbling around in the spares box I liberated a four pin header from an old Sky box motherboard and proceeded to snap it into two two pin headers.

First soldering job was to clear the two holes of the existing solder. This was easy enough with a dab of flux and some solder wick. Surprisingly, the hardest bit was soldering the pin header to the board. Holding the pins in place with my finger resulted in several minutes of inappropriate language as the rapid transfer of heat through the pin, fully complying with the expected laws of thermodynamics, burned my bloody finger. 

Trying to hold the pins with pliers proved tricky to say the least. After another minute or two of appalling profanity I manged to get one leg holding on by the merest sliver of solder. This was enough to allow me to solder the other leg and then finish the job. It's not the straightest but it's only got to hold a jumper. Annoyingly, that transistor (see below) made it tricky to get one on. A firm push of the transistor moved it a sufficient amount to remove that problem..

Lovely jumper.

But did it work? After re-assembling the case and doing all the screws up I realised I hadn't taken any pictures of the Electron in monochrome, so no Before and After pics. But here's the evidence that my traumatising injury (slightly burnt fingertip) was worth the agony (mild irritation).

Colours. (Ignore the reflected bald head.)

And now, back to those pesky cassette recorders. (Well, soon anyway.)

A Catalogue of woe...

After looking over my unexpectedly large collection of cassette recorders, I decided it was finally time to test which ones would be suitable for use with the faithful old Speccy. There are a couple of reasons. First, I like things to be original where the can be - although I'll never shy away from a faster loading mechanism if it's a good price - and second, if they work with the Speccy then there's a good chance they'll also work with my recently acquired Electron (as long as I can get a cable).

So, down to business, I went and pulled my Spectrum+ out of the box upstairs where it had been stored for the last eight months or so. Main unit? Check. Power supply? Check. Smart Card V2 from Retroleum? Check.

And then, the first problem. Powering up I was greeted by the happy beep of the Smart Card but I couldn't move the cursor up and down to select a game. How odd. I switched off, removed the SC and powered back up. Much to my disappointment and annoyance a large proportion of the keys had stopped working. This should not have been a surprise since it was still the original membrane but I had spent a long time 'tuning' the keyboard to keep it going and it was actually 100% working when I put it away. Sadly, the tails are now too far gone and it's game over for this membrane.

Tails, tails, tails

I hate this keyboard

But no problem. I already have a new membrane that I bought a while ago. It's been sat in a drawer for about a year. Out it came. BUT. This one has corrosion on the tails too! What. The. Heck. For some reason, this membrane is suffering the same fate as the original despite only being a year or two old. I put it into the Speccy to see whether I might be lucky. I wasn't. Almost the same amount of keys just did not work.

Corrosion on modern membrane

Look at the two outer tracks
Brown, not gold..

At this point it was time to give up on the Spectrum + so I removed the Z80A and re-installed it back into the CPC that it had originally came from. See the results of that, here.

Plan B. Get the 48K rubber keyed Speccy out of storage and use that. So, out it came. It's an Issue 2 but we won't hold that against him. The 3D printed case I have for my Smart Card V2 (as provided by my awesome brother) lifts the rear of a standard 48K case off the desk, but that's fine. It's only for testing stuff and it's fairly stable anyway.

Turn it on. Oh, for fudges sake. It won't boot. It's stuck on a black screen with a white border which screams of a RAM issue. So I switch the SCv2 to Diag mode. But this also struggles to boot although, fortunately, this was just down to a dirty edge connector (we've all been there!). A quick rub down with some IPA and cotton buds and the diagnostic ROM boots successfully..

Dangnabit.

...and promptly identifies IC 18 as suspect. 

Curse you IC18!

So out comes the de-solder station.... 

I have a distinct Hal feeling.

Anyway, the de-solder station makes light work of the suspect RAM IC. In a few minutes it's removed and a socket installed in it's place. 

Heath-Robinson RAM Tester

But this is a good excuse to get my RAM tester out of the drawer and check that it actually IS the problem. And sure enough, the RAM tester says it's fine. Wait? What?

That was unexpected. The RAM tester thinks this chip is OK but if I put it back in the Speccy I just get a black screen. Something is clearly affecting the result. But that's for another day. For now, let's just get a new RAM chip in the socket and see if it will boot. And then I realised the only RAM I had is a couple of chips of the infamous 'MT' variety. Known for being crap, but I had no other choice and it would only be for a few minutes of testing. Urgh, I feel dirty putting this chip in there but, sorry buddy, it's only for a short time. In fact, I was so embarrassed about having to use these pariahs that I didn't even take a photo of it. 

But does it now work? Yes, yes it does. :)

Testing, testing.

Annnnd, we're back in the room.

There is no way that I'd ever leave one of those MT chips in there so I needed to find a solution. Fortunately I had a stash of Sanyo 33256 chips which came from an old and decidedly broken A501 512Kb Amiga expansion. The pinout for these chips is virtually the same although they have a higher memory capacity, and consequently an extra address line at Pin 1. I thought long and hard about whether I should try to use one of these. Eventually, my ancient, addled brain decided that I could either pull Pin 1 out of the socket or connect it to ground and it should work. And would you believe, pin 1 on the upper RAM chips is connected to ground by default.

The only other difference was pin 9 which is A7 on general RAM chips of this type but is labelled as 'AR' on the Speccy. Basically, the original chips in the spectrum were specifically chosen as they had a fault on one bank of 32K of their 64K. As a result, Sinclair apparently got them cheaper but it means that the original chips have to match which bank is faulty. In this case, it's irrelevant as the chip is fully working with 64K (well, 256K really). It just means the Spectrum will only use one half (or quarter) of the chip. 

Here goes:

Sanyo to the rescue

Yay! It works!

Boo! The picture is, to coin a phrase, complete garbage. It's difficult to convey how back the picture really was on this thing. Imagine the worst RF output you can, then make it a bit fuzzy, lose all colour (except a big smear of dark blue across the whole screen) and you'd be somewhere close.

Sadly, this is an Issue 2 which has a deserved reputation for this due to it having manual picture controls. Later revisions had an automatic circuit built in so the variable resistors next to the ULA (pic above) are not in there from Issue 3 onwards.

Fortunately I have a shiny new sillyscope - which is actually a generous donation from my Boss. Let's see what we can see.

Composite TV signal ahoy!

So the big dips are the 'back-porch' which tell the TV, "I'm about to start a new field'. Then the squiggle to the right of the dip is the colourburst. As the name suggests, this contains the colour information for the field. Finally, there's the main part of the field. Compare this to the display at the time:

Bad colour. Smudgy. Urgh.

To improve this the variable resistors need to be tweaked to get the video signal as 'flat' as possible. This is easiest with just the white boot screen, rather than the busy screen I had up. Once I took out the SmartCard and booted up to a plain white screen, it was much easier to see the fuzzy nature of the signal.

There is a very, very narrow sweet spot for VR1 and VR2. Once it's there, it's great. You can see the result on the sillyscope below:

Ahh, that sweet spot!

That's better.

So, now I have a working ZX Spectrum with RAM fixed, clear(ish) picture and a queue of cassette recorders to try.

Except, I don't have any mono audio cables...

FFFFFUUUUU...

Next time, I butcher a stereo audio cable and finally get a cassette to load into this Speccy (preview image below!).

Ah, the nostalgia for those raster bars..

Can you hear me, Mother?

 About three years ago I acquired a pair of Amstrad CPC464s. One I sold on to help pay for the initial outlay on the bundle (which also included my Plus/4) but I kept the other as it wasn't in the greatest condition and I had, to be honest, never owned a CPC before.

Clear the decks! It's huge!

As part of my escapades with the CPC, I added an audio in mod. This allows me to load games via the sound output of my phone - or anything else with a 3.5mm audio jack. Unfortunately, I'd found that it was quite unreliable and would not load a lot of the games I'd managed to find on the internet. I put this down to the software I was using to convert the .cdt format files to .wav format being a bit flaky and my phone not outputting the volume loudly enough. And so I put the CPC away for a long while; I even pinched its Z80 processor to assist in the diagnosing of a poorly ZX Spectrum +.

Oi! That Z80 is MINE!

Z80 restored and ready.

Fast forward a couple of years and there is a rather excellent YouTube channel called "Noel's Retro Lab". As the name suggests, a very nice guy called Noel repairs and explores retro computers and games systems. And as luck would have it, he dedicated a whole video to the exploration of modding the CPC with an audio in jack. See that HERE.

To cut a long story short, my original mod was incorrectly fitted. I had attached the inputs to the actual cassette read head. While this did work it did have a couple of disadvantages. First, it seemed to need the 'Play' button pressed to pick up the input. Second, as mentioned above, it wasn't very reliable. 

The NRL video is very detailed and well worth a look but, very simply, by moving the '+' side of the input to the correct side of capacitor C317 (the red wire), this meant that the input signal would pass through the op-amp circuitry of the CPC, giving a strong and stable signal at just the right location. And no need for the tape 'Play' button to be pressed.

New wiring - thick black
and red wires re-soldered

I also moved the black negative wire from the play head to a more generic 'ground' connection. It probably wouldn't have made any difference but not really worth taking the chance.

And now... how to be a complete freakin' moron.

As suggested, I also have a ZX Spectrum on my bench which I was originally going to try with my batch of cassette recorders. I had problems though (another post inbound on that) so I re-focussed on the CPC. 

But guess what happened. I had two power plugs on the bench. One was 5v max current of 3A with centre positive plug, the other was 9v max current 1.4A with centre negative plug. When I plugged in the power and switched the CPC on, nothing happened. Guess which one I had plugged in to the CPC? (I'll give you a clue - it was the wrong one.)

!

Oh. S**T.

Fortunately, my immediate incompetence was saved by past me making the competent decision to unplug the 9v 1.4A centre negative supply from the mains. Bullet well and truly dodged.

Anyway, with power now sorted it was time to see if the mod now worked. Since it was a long time ago that I last used the CPC I had long since lost the .wav files I had of the couple of Amstrad titles I'd found. My hard disk has also been changed out in my laptop for a nice shiny SSD following a hard disk failure too so I no longer have the software that converted the .cdt files to .wav. I finally managed to find an Android app called Tapdancer. This takes the .cdt file and plays it directly out of the headphone socket of my phone. It's quite old though, and is not on the Google Play store. As a result I can't really recommend it but it did work for my test purposes.

Next problem. Finding something to load. Eventually I found a .cdt of a Spanish motorcycle racing game. Google is your friend.  Tapdancer happily accepted it and converted it but, would it load? No. Not initially. The problem though was that the cable I have kept popping out of the headphone socket on my phone. I suspect it has 'had it'. A bit of fiddling later I managed to get it to stay in.

Would it work on the second attempt? Yes. Flawlessly.

Speccy photobomb

It works!

On the first load I realised the game was in Spanish with no English option. This was a problem when I re-defined the keys and ended up with the directions and acceleration all mixed up. Not the easiest game to play with keys like that.

Next up, WEC Le Mans. And it was the English version so I could at least get the keys re-defined correctly. 

I like all racing games. Even this one.

And, again, it just worked. After about five minutes the game started straight up with no complaints. The game itself seemed OK for the time i.e. it's no Gran Turismo. With only one apparent track and quite hard time limits it's quite difficult but the graphics are cute, especially when you crash and the controls are OK, if a bit slow. I'd give the game a solid 6.5/10. 

And that's basically it. The CPC now works quite happily with .cdt files playing directly from my Android phone. The only thing I have left to do is find that piece of software I originally had that converted .cdt to .wav in case I feel the need to try a direct player (instead of TapDancer).

The CPC is also proving to be the most solid and reliable machine I have. Nice.

iMac G4 Shenanigans

We all tend to look back at events and things in the past with slightly rose tinted spectacles. I remember looking through my Grandad's old Cine films looking for 'the parrots' bit. This was where he had been on holiday in Majorca sometime in the early 80's and one of the locals had a parrot show where the parrots would do various funny things for the amusement of tourists. Growing up, I thought that this was the absolute best thing I had ever seen and it was a staple when visiting Nan and Grandad. Fast forward fourty years and I was sad to discover that that bit of footage was only about three minutes long and was, to be honest, a bit underwhelming.

And, after the excitement of getting the thing working, that pretty much describes my first experiences with the iMac G4. Underwhelming. (But that's not the whole story...)

I know that it's 19 years old. I understand that. I realise that technology has marched relentlessly forward; the web has changed, encryption and security have improved. I get all that but for some reason I was expecting more from a machine that at launch cost $1799 (almost $2600 in 2021 adjusting for inflation).

The Interwebs

So, anyway. First things first. What was the iMac G4 like to use on the modern internet? Well, if you read my previous post on this machine, you'll know that I actually managed to download quite a few things, and after a bit of work I managed to find a modern-ish browser that will load modern websites. 

First up, Twitter. Well, it works. I can't deny that. But you would need the patience of Job to be able to cope with using it. On a modern PC the twitter page updates itself every so often which is quick, seamless and unnoticed by most users. On the G4 it's slow, slow and then decides to slow down a bit. Typical time to render the home page is around 80-100 seconds. Every time it updates. Every time. Not really usable and only worth the novelty value.

Next up, Facebook. Well, this one refused to log me in. It got further than the ancient version of Safari but point blank refused to go past the login page. Oh dear.

Blogger. This one appeared to work but was, as twitter, excruciatingly slow. Then the version of Firefox I have on the iMac crashed. Ah.

At this point it was time to give up on any idea of using this for any type of web browsing. The 800Mhz processor just doesn't seem up to the job. 

Now what?

VNC

One thing that occurred to me is that, although this machine doesn't have the grunt for modern uses it doesn't need much grunt for the famous VNC Viewer. If I could find a VNC viewer that runs on this iMac then maybe I could use it to control another, more powerful machine that can be hidden away. Part of my issue is that both Mrs Crashed and I love the way the iMac looks and it's currently sat in our bedroom, just looking cool. But to be useful it really does need to be able to access the internet. No other machine is ever likely to be permitted in the halo'd confines of the bedroom, so don't even suggest it..

So, my ridiculous plan. Set up a headless Raspberry Pi with the desktop gui and VNC server enabled. Then, assuming VNC viewer is available for the iMac, connect via VNC and use the web browsing capabilities on that machine. It doesn't need to do much, just BBC News, Blogger, that sort of thing.

After a bit of Googling (or Safari'ing) I found that VNC viewer for PPC was available from here. Installation was simple and done in two minutes. After setting up my Raspberry Pi with VNC Server, it just worked. I managed to pull up the screen of the Pi and re-size the window so Chrome appeared as it would as if it were a browser window running native on the iMac. All in all, despite being a compromise, the results are quite good. No YouTube though.

Other Internet Options

The most excellent @ActionRetro1 on Twitter (and YouTube) has made a couple of websites that are designed specifically to run on very old, vintage computers. Although my iMac is possibly a bit more modern than was originally intended, the outcome is a very usable system. The websites are:

• frogfind.com
• 68k.news

68k.news

frogfind.com

As the names suggest, frogfind is a very lightweight search engine that uses DuckDuckGo as it's engine, and 68k.news aggregates news stories into simple text, meaning that viewing and reading is simple, fast and also ad-free. Both are really worth a look if you have an old machine on the intertubes and they prove that you can enjoy some online action if you don't fancy messing about with that VNC nonsense. They also work very well on modern machines if you're sick of all the ad-induced slow down. My iMac G4 displays both sites quickly and perfectly in the ancient version of Safari that is installed.

Games

Another reason for having this machine is to play games from the era. One such game that I have on PC and really do enjoy playing is Sim City 3000. This is one of the last decent versions of Sim City and is before the company that shall not be named got hold of it and screwed it into the ground. Having found the appropriate files to download I was a bit disappointed to see that the installation would not work as I did not seem to have the 'Classic' environment installed.

Dangnabbit.

After some research I discovered that the iMac PPC machines could run MacOS9 and earlier software in OSX but they needed parts of OS9 installed to be able to do so. In my installation I didn't have this, hence the failure to run the installer for Sim City 3000. When I got the iMac I did a fresh installation of OSX 10.4 which did not (or at least I can't remember it) give me any options to actually install or set up this functionality.

Below is the procedure for how I manged to install the Classic environment and make it work. I have recorded it here as it took me bloody ages to find it out and it needs a specific file to be downloaded from the Apple website. The link for that file is here but note that I can't guarantee it'll be there forever as it seems to be one of the very few bits of MacOS support that they haven't just binned from the website.

1) Download the file either directly onto the iMac desktop or copy it onto the desktop from a USB stick

2) The file is a .dmg file so mount it as you would any other disk image (on your Mac - duh!)

3) Head to the 'English' folder and look for the file called 'NetBoot.pkg'.

4) Right click (or ctrl+mouse button) and choose 'Show Package Contents' from the menu.

5) Go to the 'Contents' folder, then into 'Resources'. Find the file that is named 'NetBoot.pax.gz' and drag it onto the desktop.

6) Double click the file and extract the folder named 'NetBootInstallation'. If you get an 'Access Priveleges' error then you need to give yourself read/write permissions. Do this by right clicking (or ctrl-left click) and click 'Get Info'. In the window there's a section that says 'Ownership and Permissions'. Set it to 'read and write'.

7) Open the NetBootInstallation folder and find the file called NetBoot_HD.img and double click it to mount.

8) Find the 'System' folder and drag it to the iMac's hard disk.

9) Finally (phew!), go the 'System Preferences' and on the 'Classic' pane, click 'Start'. 

There should be some update messages, I certainly got a few, but after a minute or so the Classic environment should be running and voila! You should now be able to run Classic MacOS software. (Steps based on an original post from the Apple forums located here.)

Did it work for Sim City 3000?

Oh, yes. :)

Conclusion

The iMac G4 looks cool. It does some stuff OK but there are compromises. It's an OK retro machine but, even though it may still look modern, it is not so don't expect too much of it. With a bit of work it is an entertaining (and cool looking - did I mention that?) machine to use. If one comes along cheap, it's worth a shot.

Compact Cassette Cornucopia

 I got lucky on eBay again. Twice. First, I managed to bag a Philips D6310 cassette recorder for a fiver. This is a chunky cassette recorder that I'd intended to use with my Spectrum+ (see, there is a link to retro computers!). It was a bit bigger than I expected when it arrived but it looked cool and, initially, played cassettes fine, just needing a bit of a clean and a new belt.

But then disaster struck. One of the main drive cogs disintegrated. It was literally the consistency of chocolate and after playing 'We Didn't Start The Fire' a few times from Mr Joel, it gave up the ghost and chewed up the tape as a result. Fortunately, the tape survived. The cog did not.

To see what happened I took it apart (as you do) as the affected cog was buried deep inside, and ended up with a large bag of many, many pieces. This particular cassette recorder has its mechanism primarily constructed of plastic and is fully auto-stop on all functions. As a result, once I had it apart, I wasn't convinced I'd get it back together again - not that it mattered as I would never get a replacement cog in any case.

So, second stroke of luck on eBay. I saw a job lot of five cassette recorders on eBay and managed to bag the lot for £5.50. Bargain. The machine I'd specifically been looking at was the WHSmith unit. But I'm getting a bit ahead of myself.

BARGAIN!

By the time the magical box of five cassette recorders arrived, I had found that someone had a 3D print available on Thingyverse of the offending cog from my D6310. (Interestingly, the same cog was used for many Philips cassette recorders.) And who should have a 3D printer to hand? My illustrious brother. After a few days a pack of six resin printed cogs arrived. Two were immediately rejected as some teeth had broken off. But that left four candidates that could potentially bring the D6310 back to life.

By this point, and much to Mrs Crasheds amusement (she was not amused), I had six cassette recorders in need of various things. They were:

Philips D6310

• New belt needed
• Drive cog stripped
• Needs a clean
• In a million pieces - put it back together!

A ) WHSmith CPD8300

• New belt needed
• Buttons Broken
• Runs very sloooow

B) Sanyo DR-101

• New belt needed
• Needs a clean

C) Sanyo M-787AG

• New belt needed
• Mechanism VERY noisy
• Fuse blew during testing

D) Bush (Rank)

• New belt needed
• Needs a clean

E) York Radio Cassette

• No sound
• New belt needed
• Really needs a clean

A to E as above

I shall cover the other machines in another post but, first things first. Let's get the D6310 back together..

A small cog in a large machine

An appropriate cog was selected to replace the chocolate one. As the picture shows, the original really is shot to pieces. Next, I laid out all the pieces to understand the scale of the problem I'll be facing...

Your leg bone's connected to your ankle bone..

Getting the transport mechanism together was not as difficult as I had originally expected. I had, by some good luck, managed to find the D6310 service manual and there is also a fantastic website with some good quality photos of a unit that I could also refer to. The new cog can be seen on the right side next to the capstan in the pic below..

Piecing it all together...

After an hour or so I had the transport mechanism back together. As it turns out, the only mistake I made was the auto-stop lever ended up on the wrong side of another levery thing so it went clunk clunk clunk instead of just click. This excellent website helped me out here too, with me realising my mistake eventually while reviewing the photos available.

A few points:

That spring at the front of the mechanism was a real pain to get in correctly. It's really strong and has to sit at the bottom of the post it sits on or everything will just not fit and then spring off into the carpet.

The mechanism is all plastic but is surprisingly robust.

I forgot to re-install the Pause button bar and had to remove the buttons and do it all again (including that bloody spring).

Back together
Now with added Pause bar!

Finished!

After I managed to get everything back together it was time to test it. I was concerned that the cogs that had been 3D printed might not be up to the task. But these were resin printed and, so far, the one I selected has not broken. The player is quite noisy though which I suspect is because that cog is much harder than the original. It could be that the material of the original was specifically selected to reduce noise. But it works!

Now I just need to find the time for the other five, and that's before I test them on a Speccy!