Lyonsden Blog

Category - Vintage Hi-Fi

Cassette Deck Maintenance: Demagnetising a Tape Head

Binatone Data Recorder - Demagnetising Tape head

In addition to regular cleaning another vital part of keeping your cassette deck running smoothly is demagnetising the tape head. This applies to both computer cassette decks and Hi-Fi ones. Over time a residual magnetic field can build up on the head. Not only can this adversely affect playback (more noise and loss of high end response) but it can also degrade the quality of any tape passing over it.

A cassette tape is basically a strip of thin plastic coated with a ferrous material. Music (or data in the case of a computer tape) is recorded onto it by using an electro-magnet to magnetise the tape surface to varying degrees. A tape can be erased by placing a strong magnet near it so even a weakly magnetised head will, over time, slowly erase any recordings passing over it. The more you play a tape on a deck with a magnetised head, the greater the cumulative effect will be.

TDK HD-01 Tape Head Demagnetiser

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So what can you do about it? Well thankfully there are a number of different ways you can demagnetise tape heads. Popular methods include a mains powered electro-magnetic wand and those cheap cleaning cassettes that contain a rotating magnet on a little disc. In the past I relied on an the latter; an old Maxell cleaner/demagnetising cassette. However just recently I stumbled across this TDK one advertised as ‘New Old Stock’. I’ve always trusted TDK as a brand, they make good quality products and know their stuff. It was a little on the expensive side due to me needing to pay shipping and import taxes from the US but I felt it was worth it.

 

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Although the box it came in was very tatty, the contents were like new. Inside there was a small instruction manual and the demagnetiser itself. The device is powered by a small 1.5V lithium battery which should be good for 500 uses according to the instructions.

Naturally I had to install a new battery before I could get it to work. The rear of the instruction manual is stamped with the year 1978 so this little gadget is now over 40 years old! Thankfully it takes a standard size A76/LR44 button cell battery that is still readily available.

 

How does it work? – Demagnetising the tape heads

So how do you use it? Well it really couldn’t be any simpler. You basically pop it into your cassette player and press play! There’s a small plastic micro-switch above the play head that is activated by the motion of play head moving upwards when you press the play button. A red LED illuminates at the centre of the cassette to demonstrate that it’s working and that’s it, job done! When activated the circuitry inside the demagnetiser generates a pulse signal which demagnetises the play head in a matter of seconds.

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There’s a little more to the process than that if you are using the device in a cassette deck that doesn’t have a mechanical play button. The device won’t work until the play button is pressed so if you have a deck that won’t allow you to press play whilst powered off then you need to take a few precautions. This is because of the strong signal it outputs which can damage amplifiers and headphones if you don’t make sure to fully turn down any volume controls first. My Hi-Fi has a fully electronic transport mechanism so I have to be careful when using it on that device for example.

 

Commodore C2N - Demagnetising Tape head

Commodore C2N – Demagnetising the tape head in progress!

 

Thankfully most older devices have fully manual play buttons and need no such precautions. With devices like the Commodore C2N Datasette I can simply pop the cassette in, press play and the get the job done in seconds. I would imagine virtually all Walkmans would be equally simple to work with.

The manual recommends demagnetising your tape head every 30 hours of playing time. Therefore, how often you need to do this will depend on what sort of tapes you are playing and how often you play them. For my Hi-Fi deck regularly playing C60 and C90 tapes this could be as often as once a fortnight. For my computer decks playing relatively short C15 tapes much less frequently, once every 6 months would be more appropriate.

Despite the cost I think the device is totally worth my time and money. Given how precious some of my old cassette tapes and games are to me, anything I can do to help prolong their lifespan is worth doing in my book.

Retro Grooves 3, a MiniDisc release in 2019!

Retro Grooves MiniDisc

As a fan of Anders Enger Jensen’s other releases I’ve been looking forward to Retro Grooves 3 for quite some time now. What I was not expecting at all was for him to release this on MiniDisc! When he emailed me to let me know it was coming out on this format I just had to get it, as well as the cassette version!

 

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Both versions are really professionally presented with full colour inlays that unfold to reveal a lot of interesting information about each track. This is something you just don’t get with digital music. I loved being able to listen to each track for the first time whilst browsing Anders’ notes about what inspired him or the processes involved in creating a particular track.

 

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He’s certainly pulled out all the stops for the MiniDisc release, the artwork on the disc has been printed directly onto the case itself – no cheap stick-on labels here. This is certainly the only MiniDisc in my collection that has been printed this way and it looks amazing! The cassette release still looks good too, coming in a transparent green case with the album details printed on it in contrasting white.

 

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A lossless digital download of the whole album is included with both the Cassette and MiniDisc formats. Additionally the digital download includes an extra 16 bonus tracks not included on either the tape or disc releases. Alternatively, if you don’t mind missing out on the physical formats completely you can opt to just buy the album digitally if you prefer.

 

Retro Grooves MiniDisc

The entire Retro Grooves cassette collection to date…

 

Verdict

Regardless of which format you choose, if you enjoyed either of his previous Retro Groove albums, or even Troubled Hearts then I pretty much guarantee that you will also enjoy this. Anders’ signature style of upbeat ‘cheerful’ sounding synth music mixed with occasional samples is present and correct. My personal standout favourite track has to be ‘FM Love’ closely followed by ‘Isabella’s Dream’ which features some lovely harmonised female vocal samples.

 

Retro Grooves MiniDisc

MiniDisc version includes full track listings

 

There’s a couple of tracks with backing singers this time around that you may or may not enjoy depending on your taste. ‘Escape Your Fear’ sounds like it could have come straight from the Troubled Hearts album and I really enjoyed it. The other, entitled ‘Let’s Fly’, I didn’t like so much as the vocals are very processed and it just didn’t really click for me. It wasn’t bad enough that I’d want to skip it, but it’s definitely not something I’d want on repeat.

Anyway if you would like to get hold of a copy for yourself than head on over to EOX Studios website.

AIWA HS-PC202 Mk3 Cassette Player – Replacing a Drive Belt

AIWA HS-PC202

Introduction

I recently bought a ‘New Old Stock’ AIWA HS-PC202 Mk 3 Personal Stereo off eBay as I just couldn’t resist the idea of unboxing a ‘new’ walkman in 2018. Now I’m fully aware that you can buy brand new ones off Amazon but these are pretty cheap and nasty affairs designed to cash in on nostalgia rather than offer a quality audio experience. This Aiwa model is a quality bit of kit with the ability to play Chrome tapes, Dolby B & C noise reduction, auto-reverse and a super slim, attractive design.

However it had been sat in storage for about 25 years so when I popped in some batteries and tried to play a tape – nothing happened! I could see the power LED light and hear a hiss from the headphones but the spindles didn’t turn. Thankfully I could hear the motor run momentarily if I held the unit to my ear whilst pressing ‘play’. This was a sure sign that the belt had failed in some way which is very common on vintage cassette decks.

This post will provide instructions on how to open up the AIWA HS-PC202 Mk 3 cassette player, and replace the belt. The only tools you need are some small watch-makers screwdrivers and a pair of tweezers. It’s quite a straightforward job as the player has been designed with the foresight that one day someone would need to change that belt!

Getting Started with your AIWA HS-PC202

The first thing you need to do with your AIWA HS-PC202 is unclip the battery compartment as one of the screws you need to remove is hiding behind this. Now you need to remove the backplate from the player to expose the belt. It is held in place by 3 tiny screws and a clip that fits inside the case near the play button.

Take your philips screwdriver and remove the first screw shown in the picture below. Place it in safe place, preferably in a small container as the screw is incredibly small and easy to lose. This is a slightly different size to the next two so it should be easy to identify when you are putting things back together.

AIWA HS-PC202

Remove this screw first

Now spin the player around so you are looking at the side where the lid hinges and remove the two screws indicated in the photos below.

AIWA HS-PC202

Remove the left screw

AIWA HS-PC202

Remove the right screw

Removing the Backplate

Store these two screws safely with the other and put aside as you are ready to begin removing the backplate now. You need to be careful and not rush this next part as there are a few things that are held in place by the backplate and they will fall out and get lost if you’re not careful. The one thing seems to fall out no matter what you do is a small, circular, black plastic spacer that fits between the backplate and the DC power socket. Now you know about it, be prepared for this and catch it. Store it safely with the other screws.

The other things held in place by the backplate are the Dolby NR and Tape Bias selector slide switches. It’s simple to put them back if they fall out – but if you’re not expecting them to drop out they could easily fall on the floor un-noticed and get lost.

AIWA HS-PC202

This is the small plastic part that will fall out from around the DC power socket.

tiny bits of plastic

These are the Bias and Dolby selector switches that may drop out when you remove the backplate.

The backplate needs to pivot away from the case from the battery end first. There is a lip at the opposite end by the volume wheel and switches so you need to picture it hinging from that position and focus your efforts on making it open that way. If you place your AIWA HS-PC202  vertically it’s easier to do this and it will prevent the switches from falling out.

AIWA HS-PC202

Gently prise the backplate off, starting at the battery end (the bottom in this photo)

As you can see in the above photo there is a small metal tab on the front edge of the backplate that fits into a plastic lug inside the case, above the play button. You will need to carefully slide a small flat bladed screwdriver in and gently lever the plastic around the play button outward, away from the backplate to release the tab. The backplate should now be free and you can pull it away from the body and slide it upward to remove it, leaving the switches on the top in place.

backplate

The backplate – note screw holes and cut-outs for controls and DC input.

Inside the AIWA HS-PC202 Mk3

Now that the backplate if off you should see be able to see the circuit board with a cut-out for the belt and pulley wheels just like in the photo below. A belt in good condition should be taught and fit around all the pulleys tightly, something that mine was definitely not doing!

The smallest wheel is the motor pulley, the two large brass wheels drive the capstans and I think the smaller black wheel is there just to guide the belt around the others.

AIWA HS-PC202

Inside the player. See how the rubber belt is no longer taught and is just lying there looking lumpy and uneven

Replacing the Belt (Take 1)

It took quite a lot of investigative work to locate a new belt that was an exact match for the original. Avoid those cheap multi-packs you can pick up off Amazon and eBay from China – the quality of them is variable at best and the chances of getting one that actually fits correctly is next to zero.

The belt fitted to this walkman has a square cross-section, not round or flat like many other belts. It is also very thin – about 0.6mm thick. The length is 76mm. For belts most suppliers use the measurement of the diameter of the belt when laid out flat in a circle. So basically you need to find a 0.6mm x 76mm belt. I couldn’t find one this thin at first so I bought a 1mm x 76mm belt. It did fit and work but was quite a tight fit around the black wheel where it nearly touches the side of the case. It was also only a fraction of a mm away from touching itself (ooerr) where it passes beneath the nearby brass pulley (see the photo below to see how tight it was).

The company I bought the belt from (SignalsUK) was super helpful and based in the UK too. The belt arrived a couple of days after ordering. Although it was thicker than the original it did appear to work OK. (Edit: Sadly this company no longer appear to exist (at least online) so I’ve removed the out of date link to their site).

The belt is very easy to fit. Use your tweezers to place it around the motor spindle and around the other pulleys following the path in the photo below. There is a small plastic tab that protrudes out of the case towards the black plastic wheel. The gap it leaves is very small (you will find it at around the 8 o’clock position) so be careful not to snag or damage the belt here. There will be a a degree of tension in the belt and this is normal so you will need to stretch it a little over the final wheel.

AIWA HS-PC202

The 1mm thick belt – notice how it is practically rubbing against itself where it passes back beneath the left-hand brass pulley wheel.

Replacing the Belt (Take 2)

If a jobs worth doing, it’s worth doing properly – so I continued my search for a better fitting belt. Eventually I stumbled upon a place that custom manufactures belts for a variety of machines, including the AIWA HS-PC202 Mk3. The Mk3 is apparently mechanically identical inside to the Mk2 and so the belt they supply for the Mk2 also fits the Mk3. Here’s a link straight to the correct belt – here. The company, FixYourAudio, is based in Slovakia and is run by a very helpful guy who makes the spare parts purely as a hobby to help enthusiasts keep these old machines alive. A week or so after ordering my belt arrived in the UK so I have no qualms in recommending them. It is ever-so-slightly thinner than the original but is definitely a better fit than the 1mm thick one.

belt path

New 0.5mm belt fitted

belts

Comparison between the old stretched and worn belt on the outside and the new one on the inside!

Putting it back together

Before you finish off – if you have any additional problems with your player such as unwanted ‘scratchy’ noises when turning the volume wheel or when the headphone jack is twisted in the socket then take advantage of the opportunity and squirt some DeoxIT on them whilst you’ve got the player open. Don’t forget to operate the volume wheel fully a dozen or so times to work the fluid into the pot and clean it up. Likewise for the headphone socket, squirt some in and then insert the plug and twist it around in circles a bunch of times to clean off the contacts.

Now you just need to put it all back together. If you knocked off the slider switches then pop them back on now. You will notice that one side of them is hollow and this will sit on top of the appropriate switch sticking out from the circuit board. The larger of the two fits on the Dolby NR slider whilst the other belongs on the Tape Bias switch. Don’t forget to place the little round spacer back over the DC input port. There is a little flat spot on one side of the circle and this should be positioned facing the outside of the case so that it fits flush against the flat edge of the backplate.

back off

View of the controls – note the small white Bias and Dolby switches. It is on these that the black ‘cross’ pieces will sit on if they have fallen off

You may need to press and squeeze gently in a few places, particularly around the play button to get the tab to engage in the lug correctly. However you should not have to force anything. If you feel any resistance stop and check, reposition the backplate, check the spacer and/or the position of the slide switches and try again. Once it has popped back into place and you are happy with the fit all around, replace the 3 screws and you should be good to go! Enjoy the new lease of life your personal stereo has been given!

AIWA HS-PC202

The small plastic spacer fits here. Flat edge towards the backplate.

If you found this guide to replacing the belt in an AIWA HS-PC202 useful then please leave a comment below, it would mean a lot to me. Likewise if you have any questions I’ll do my best to help.

If you’d like to know how to go about de-magnetising the play head in your AIWA HS-PC202 then take a look at this post.

Retro Grooves volume 2

Retro Grooves vol 2

Retro Grooves vol 2 is something I’ve been looking forward to since I first heard Anders was working on it as I loved the first album. As usual it comes on a really awesome professionally presented cassette tape with a lossless digital version included with your purchase. You can also just buy the album digitally if that’s what you prefer.

Personally a big part of the pleasure of getting this album is the fact that it comes on an audio cassette. I love opening the cassette, unfolding the inlay, reading about each track and of course popping it in my cassette player to listen to it. It all adds to the experience whilst not being able to skip tracks encourages listening to the entire album instead of skipping through to find instant gratification.

Verdict

I’d say it was a little more mainstream than vol 1 as there aren’t as many chip tunes but if you liked the first album then you will no doubt like this too. I really enjoyed all the tracks except for the MarioKart 64 Remix where I found the Mario samples to be a little annoying. But who knows, maybe it will grow on me in time! Some of the tracks will be instantly recognisable if you watch ‘The 8-Bit Guy‘ on YouTube whilst others will take you straight back to the 80’s with riffs that wouldn’t be out of place in an episode of Miami Vice. Definitely recommended anyway and I personally can’t wait for vol 3!

If you would like to get hold of a copy for yourself than head on over to EOX Studios website.

Retro Grooves vol 2

Cassette tape with folding inlay

 

Retro Grooves vol 2

Retro Grooves vol 2 playing in my Sony WM-D6C Walkman