Bush TP79 cassette
 

Hello all

I've just picked up a Bush TP79 cassette player for the princely sum of £2.

While I am no fan of cassettes usually, I am a Bush fanatic, so I had to have this one.

Does anyone know where I would get the service data (seems not to be up top) and where I might get belts for it (I am presuming they will need sorting.

In truth I am hoping there's not much up with this as I don't feel up to trying to work on something so complex (by my standards).

Martin

Re: Bush TP79 cassette
 

Re: Bush TP79 cassette
 

That's great, thanks.

Re: Bush TP79 cassette
 

Hello again all

I have got service data for this machine now (yes, I know there's a big gap between the last post and this!) but the only extract I have been able to get my hands on does not include information on the belts.

I've not opened the machine up yet but I presume the belts will need changing (after so long surely they will be in a somewhat suspect state).

What's the best way to go about souring belts? I see that on ebay and BangGood etc there's various multi-size selections - is that they way to go or is it better to measure up the exiting belts (presuming that they are up to it) and getting specific sizes?

If, and it is an if, this one goes OK then I may pick up more small machines to play with, so a batch of belts would not necessarily be a waste.

Martin

Re: Bush TP79 cassette
 

Buy a bag of assorted generic belts, e.g. https://www.ebay.co.uk/itm/Mix-Casse...EAAOSwSv1Xlbv5

There's a good chance there will be everything you need in there. Even if you find you need a more specialist flat belt for the capstan, the generic belts will make it easier to work out the size required. I buy one off belts from CPC.

Re: Bush TP79 cassette
 

Thanks Paul - there's no risk there is there at that price.

I saw a video on YouTube where some chap had replaced the belts with elastic bands he found around the home. I won't be doing that of course as I expect they'd go sticky pretty quickly.

Re: Bush TP79 cassette
 

OK, belts ordered.

I have found that the power socket, rather than being fig8 as I thought is actually a rectangle not wide enough to accept my generic lead. I'm not familiar with this plug - is there any sort of adaptor for this or should I go down the battery route?

The power input is 240v, batteries 6v - safer I suppose :)

Re: Bush TP79 cassette
 

I would get it working on batteries, then sort out the power side.

Re: Bush TP79 cassette
 

Martin,

Quote:

The power input is 240v

IMPORTANT !!

Are you absolutely/100% sure that the 'socket' is for 240V AC, does it say or is it printed somewhere ???!! Sometimes, where the 'socket' is fitted, it should printed on the case, nearby.

The reason for this question is that, this type of connector was used mainly in the 70's and very popular.

But, unfortunately, some manufacturers used them for mains input, whilst other manufacturers used the very same 'socket' for use with an AC to DC adapter.

This lead to major & dangerous problems. i.e. A lead which was designed for use to supply mains voltage to an AC machine could also be plugged into a machine that was designed only to run off an AC to DC supply. The result, to the AC/DC version was disastrous !!

The result being the discontinuation of that type of plug & socket and the introduction of the Fig 8 type.

However, you can still but the 'plug' from CPC/Farnell into which you can fit a two core mains lead.

Here's the direct link:
http://cpc.farnell.com/unbranded/cn-...m%2Fw%2Fsearch

Re: Bush TP79 cassette
 

The warning is timely, but only a small number of manufacturers used these connectors for a low voltage connection. They were the standard mains connector for Japanese, Taiwanese and Hong Kong stuff for a few years before the 'figure of eight' connector became popular.

Re: Bush TP79 cassette
 

I am pretty sure it is 240v AC but I will check later on and report back.

Re: Bush TP79 cassette
 

If you take a look inside, you should see a mains transformer if the power input connector is for mains. Two wires from the transformer (the primary winding) will connect to the pins of that connector directly (it is very uncommon to have a mains switch or fuse in this sort of cassette recorder).

The other thing to try (without even opening the case) is to measure the DC resistance between the pins of that connector with your multimeter. If it goes to a mains transformer, I would expect a few hundred ohms of resistance between the pins. If it's a DC input, the resistance (with the machine turned off, in stop mode, etc) would be a lot higher, possibly infinite.

Re: Bush TP79 cassette
 

Hello again.

I can confirm that the power socket is for 240v AC. I will, however, start with batteries I think just for ease.

Martin

Re: Bush TP79 cassette
 

Martin,

By the way the connector (as per CPC link) are becoming hard to find and I think CPC will discontinue them when stock is gone. p.s: I have no connection to CPC.

Re: Bush TP79 cassette
 

Thanks. It will be worth me getting one.

Any idea what the postage is from CPC as this is under their free threshold (if I buy just one)?

Re: Bush TP79 cassette
 

Ignore the question above - I thought I'd have to set up an account to find out the postage charges, but in the end I didn't.

Is there a sticky or thread on cassette deck servicing similar to the one on record decks? I've found that my machine works and while I plan to renew the belts and clean the tape path, I was also wondering if there's any need to clean or lubricate any of the workings.

Re: Bush TP79 cassette
 

They vary a lot so it's difficult to generalise.

I generally don't relubricate in the absence of a fault. I clean any idler wheels, mating surfaces and pulleys with meths. I reset the azimuth, and reset the tape speed using a test cassette and CD if this is reasonably easy to do. Obviously the tape path gets a good clean.

Re: Bush TP79 cassette
 

Thanks Paul.

I remember having a tape speed cassette when I worked in a hi-fi shop in the 90s (I was largely in charge of cleaning the windows and putting the rubbish out!) and was wondering if these were still available - are they? As I recall it worked in a similar way to a record deck strobe disc.

Re: Bush TP79 cassette
 

The correct way to set the speed is to use a commercially produced test tape and frequency counter, but I didn't have access to those, so this what I did.

Generate some suitable tone on a computer, and burn it to an audio CD. Record the CD onto a cassette using a known good cassette deck. Play the cassette in the deck to be adjusted listening on one ear of a pair of headphones, while playing the CD over speakers. Adjust the motor speed until the tones are the same, and then adjust for zero beat.

You probably don't need to worry about this with your TP79 unless the speed is grossly out, and it may not be easily adjustable anyway, but I normally do it with hifi decks.

Re: Bush TP79 cassette
 

Apologies for the question bombardment, but I am on a roll with this one which makes a nice change.

Cleaning tape heads, capstan and pinch roller etc - meths or IPA or either? I ask as meths is mentioned above so I suppose I know the answer to part of my question, but I have some IPA to hand. I don't want to use the wrong stuff ideally nor buy meths if I don't need to (the stuff I've had in the past has been horrible).

Re: Bush TP79 cassette
 

I always use IPA on tape heads (that's isopropyl alcohol, aka propan-2-ol, of course). It is recomended in many computer disk drive service manuals for cleaning those heads, and I have never had any problems using it on tape recorder heads.

Re: Bush TP79 cassette
 

Thanks Tony.

I have no reason to doubt meths would be ok, but I dislike it - I think I must have been cavalier in my use of it in the past while decorating as the thought of it makes me feel a bit queazy now :)

Re: Bush TP79 cassette
 

Either will be equally good for this. Meths will leave a deposit if you don't clean it all off, whereas IPA won't, but any deposit doesn't normally matter and just wears off. Meths is cheaper than IPA and the BBC used it for tape path cleaning right through the analogue era, but if you have some IPA you might as well use it. You only need a tiny amount in either case.

Re: Bush TP79 cassette
 

I suspect that pure ethanol would be fine (but of course it is difficult to get due to the posibility of making drinkable spirits with it). So would methanol (but I seem to remember that is toxic). Meths is mostly ethanonl with a bit of methanol (it is not pure methanol, no matter what some people claim), something to make it undrinkable, and purple dye. It's the last that would worry me using it for cleaning tape heads, I am not at all convinced that it will leave no residue

Re: Bush TP79 cassette
 

It does leave a residue if it just dries, but the tape abrasion removes this almost instantly in normal use.

Modern meths doesn't actually contain any alcohol other than ethanol. People will drink meths whatever you do with it, and you don't want them to die or go blind or whatever, so it's now made with industrial ethanol plus some additives that make it look and taste absolutely horrible.

If people choose to drink the stuff despite the disgusting additives then it won't kill them, though if they're that far gone then they'll probably die of something else quite soon.

Re: Bush TP79 cassette
 

I have established that the tape player works and I will be cleaning it up shortly, replacing the belts when the kit I have ordered arrives (from China, so may be 2019!).

I am also keen to see how it sounds through my hi-fi and have read in the service data that pins 1 and 4 are aux out. I am taking this to mean they are left and right audio out - would that be right? If so would it be as simple as cutting the end from an old phono lead and soldering one channel to each and one to ground (pin 3?).

Re: Bush TP79 cassette
 

I don't know this player - some photos and/or a partial scan of the service info would help. If the player is stereo, then the socket will be as you expect. If it's mono, then both pins will carry the same signal.

Don't expect this to sound particularly wonderful through a hifi system. There are plenty of good hifi cassette decks available for little money or even FOC if you want to explore the cassette world.

Re: Bush TP79 cassette
 

I have attached the part of the data that I am looking at.

As for whether I want to get into the cassette world... well I didn't, but I am intrigued by this player.

Anyone who has met me will know that I am enthusiastic but short on time and space, so doing some work on a little player like this appeals to me.

Musically I am also from a bit of a "lo-fi" background so can see the charm in this type of player. I had a pre-rec Neil Young cassette on last night and enjoyed it in all its muffled mono glory.

That's not to say I won't get a decent deck at some point. But for now this one at least gets me dismantling and soldering with some goal in sight.

Re: Bush TP79 cassette
 

That is standard wiring for a 5 pin DIN socket on mono equipment. It means it can be connected to stereo equipment and will record from and playback to it (in mono). It will also work with a 3 pin DIN mono cable.

Re: Bush TP79 cassette
 

Thanks Paul. Much appreciated.

Re: Bush TP79 cassette
 

Really pleased to hear you are making good progress on this cassette player. Great work and keep it up. These small projects are great for when time is short and fairly quick rewarding results can be achieved.
Dave.

Re: Bush TP79 cassette
 

I thought I would report back after doing a bit of work on this one.

I managed to open it up with the help of the service data and, to my eyes, the belts look and feel in good condition. I have a set on order but is it worth changing them just yet?

I have cleaned the tape path and got a surprising amount of muck off the heads and rollers.

And, after getting it back to front first time round, I've wired up a lead to get it playing through my hi fi.

I suppose now I'm wondering if that's it. The speed sounds fine, not too much wow considering the age of the player and tape.

I have to say I find DIN plugs horrible to solder up. But that aside this has been a pretty simple one.

Re: Bush TP79 cassette
 

If it's working normally and the belts aren't slipping then you might as well leave them alone. You can always replace them later if problems develop. It's always a good idea to keep a bag of generic belts handy in any case, so your money won't have been wasted. You'll find yourself using them for all sorts of things - I used one to replace a DVD player tray eject belt a few months ago.

Re: Bush TP79 cassette
 

Thanks Paul.

This is only my third real achievement so far. All three have been simple services and fixes on working-ish items, but it's nice all the same.

Re: Bush TP79 cassette
 

Meths, IPA, vodka....you can clean tape heads with all of the above as long as you know IPA is isopropyl alcohol and not India pale ale :)

Back in the day, most "tape head cleaning solutions" were 60-70% IPA. You could get "zero residue" tape head cleaner which was probably close to 100% IPA. You can still get this in a handy spray can under the Servisol brand. This is my preference these days.

Once I had to resort to absinthe at 95% ethanol....it seemed to work!

Re: Bush TP79 cassette
 

Great work, Martin.

I agree with you about soldering DIN plugs. The pins are quite close to one another and the plastic softens as soon as you apply an iron which means you can end up with the pins at jaunty angles. My way of avoiding this is to insert the plug into a scrap socket held in a vice (or similar) while doing the soldering.

The other problem is that terminals of the modern, Chinese ones don't take solder very well at all and often need to be abraded and tinned before you stand any chance of making a good connection. The older, German(?) ones didn't have this problem, though the pins were silver plated and often went horribly black.

This is before we even get onto the problem of manufacturers not adhering to the DIN wiring conventions or levels standards...

Nick

Re: Bush TP79 cassette
 

My technique, if you can call it technique, was to hold the pins in the clip on my helping hands thing and do all my prep in advance.

Then once I'd got a wire on a pin just leave it - I usually try to be neat but I knew the consequences of going back to try to tidy up. I expect my plug is a good one as I got it off the market as part of some odd lead.

Of course the lead I made is too short and now I've decided I want a play and record one, so I will have to buy another DIN plug anyway.

Re: Bush TP79 cassette
 

The instruction book of the Russian camera I bought in the 1960's recommended using eau de cologne as an alternative to alcohol for removing grease from the lens. I never did, but did use some Brut aftershave to clean the head of my rtr tape recorder when away from home with no meths handy. It certainly got rid of the oxide.

Re: Bush TP79 cassette
 

Funny you should say that. I used my remaining IPA as aftershave...

Seriously though, thanks to everyone one for pitching in on this one.

I'm now wondering whether there's any of these very small players that could be considered in any way hi-fi. I don't have space for a full sized deck and I like these little ones. Last year I passed up the chance to pick up a nice little Decca one which I regret now.

Re: Bush TP79 cassette
 

The vast majority of hifi decks are the standard width of 17" or thereabouts to match other full sized separates. There are some smaller decks made to match midi or micro systems but they aren't very common and may have mechanical issues. If you want something really small you could go for a high quality Walkman type player, though most of these don't record. One of the Walkman Professional models would be ideal (they do record) but you won't find one of those for £2.

http://www.walkmancentral.com/products/wm-d6c

Re: Bush TP79 cassette
 

I used to have a Sony pro Walkman but sold it long ago. We also used to use Marantz machines at college which were very good as I recall.

I see you can still get new 'shoebox' players.

Re: Bush TP79 cassette
 

Uher made some small cassette recorders (larger than than a Walkman, but much less than 17" wide) that were good quality both in terms of the audio reproduction and the build.

I have a CR210 (not for sale!) which is stereo and has auto-reverse in play mode.

Be warned that they can be tricky to work on, there is a lot packed into a small box, but they are worth it

Re: Bush TP79 cassette
 

I now have the required socket to make up a power lead. Before I go ahead I wanted to check something.

On opening up the socket (or is it a plug? - you know what I mean anyway, the bit that goes into the tape machine) it looks to me as though the mains cables are to be soldered in place.

Is that correct? I was expecting some sort of arrangement similar to a mains plug with screwed terminals.

Re: Bush TP79 cassette
 

They are the solder type. There wouldn't be enough room for screw terminals.

The part you have there is this description: Cable ended 2 pin socket, whereas the part already fitted in the machine is designated: Chassis mounted 2 pin plug with switch.

Re: Bush TP79 cassette
 

Thanks. As you say, it does look a bit tight in there.