Yet another Bush SRP31D restoration.

[Rat-One]

Good afternoon everyone

Mine works great, however it seems like audio is coming out from 1 channel only.
I am still not sure if the grey wire with plug should be placed in the left hole (stereo output) or in the right one(Amp input).
I am confused because when I plug it into the stereo output, is sounds good, but it feels mono, while when I place the plug into the amp input hole there is no sound at all.
Could it be a faulty cartridge?
The player has got an Acos GP94-1 mounted on, with 4 flat parallel pins
I guess the cartridge is stereo? Is it the right one?
Not sure if the wires are connected in the right sequence, anyone could help on this?

Please accept my apologies for being long, frustration is leading my actions at the moment!!

Best regards
Frank

[ms660]

If plugging the plug into the amp input kills the sound then it sounds like there's a short somewhere across the two conductors between the plug and the cartridge or the stereo socket, note that when working properly the signal at the stereo output socket is not full stereo, it's only one channel of the stereo, the left hand channel, and it's there to feed an auxiliary amplifier such as the Bush AU31D in order to get the stereo sound, might be worth checking the connections at the cartridge first.

Lawrence.

[BRASSBITS]

The reason it feels mono is because it's a mono record player.

[Edward Huggins]

Your ACOS GP94-1 cartridge is a true stereo cartridge, it is the correct type and quite a good one. Without an external Stereo adaptor, you will only ever hear Stereo records in Mono. It is important that both the LH and RH channels are bridged to allow you to hear all the content of the record in Mono.
In its default state, the Bush will give you this. I hope this is clear, if not we can add more detail.

[slidertogrid]

And the reason you get no sound from the stereo socket is because that socket is for a separate amplifier and speaker that Bush did as an optional extra to convert to stereo. the cartridge had to be reconnected for seperate stereo channels one to the internal amp and one out to the extra amp via the stereo socket. Your player as it stands has one speaker (and a tweeter which is usually not working by now).
A pic of the extra amp.
https://www.bing.com/images/search?v...6917776AAE6116

[Station X]

Originally Posted by Rat-One

Good afternoon everyone

Mine works great, however it seems like audio is coming out from 1 channel only.

Frank

It's only ever going to come out from one channel, that's all there is this being a mono player.

The question is are both channels from the cartridge going into the amplifier?

With the plug dangling you'll just hear the RH channel. With the plug in the amp socket you'll hear both channels.

[Audio1950]

The original cartridge would have been a Sonotone 8TA, so as it has been replaced, it could be simply that the wires at the rear have been replaced wrongly?

Barry

[Rat-One]

Good morning everyone and thank you for your time and suggestions.

I do understand the player will play mono unless coupled with an external amp
I just don't get why I hear nothing or just a hum when the plug is connected to the AMP socket, which should be the default one.

Perhaps Barry is right and the wires are not connected in the right order, I haven't replaced the cartridge myself, that is how I found it.

I am not too sure what the correct sequence would be, anyone could help with this?

I attached pictures of the cartridge, for reference.
The wires are blue & yellow (going to the STEREO OUTPUT socket) and red & black (Going to AMP INPUT)

Also, I found a AU51 amp unit, do you reckon it could be coupled with the SRP31 and how? They seem to have different connection types.

I hope I have been clear, I have lots to learn and my technical vocabulary is limited!

Kind regards
Frank

[Station X]

Originally Posted by Rat-One

I attached pictures of the cartridge, for reference.
The wires are blue & yellow (going to the STEREO OUTPUT socket) and red & black (Going to AMP INPUT)

Frank

Yes, but in what order are the wires connected to the cartridge? We need to be certain which the wires are connected from where and to where before moving on to fault finding procedures.

[Rat-One]

Hi Graham

I cannot find the paper where I noted that down, but I believe I had the channel with black and red connected to the outer pins and the one with yellow and blue connected to the inner ones

[ms660]

Looking at the 3rd photo..... tags from the left to the right....Yellow, Blue, Black, Red so far as I can make out.

That's assuming the connections underneath the deck haven't been altered.

Lawrence.

[Rat-One]

Hi Lawrence

So let's call the pins left to right 1-2-3-4
Yellow 1 Blue 2 Black 3 Red 4 (stylus facing down)

I couldn't find any marking on the cartridge and unlike other models I have found diagrams for, on this one the pins are in line, which got me confused.

I will give it a go when I get back from work.

Also, how do I know which one is - & +?
I know, full on dummy here!

[ms660]

Originally Posted by Rat-One

how do I know which one is - & +?
I know, full on dummy here!

L+ = Yellow.......L- = Blue

R+ = Red.......R- = Black

Lawrence.

[Rat-One]

Is this always the case?
Thanks
Francesco

[Edward Huggins]

As to using the Bush AU51 with you record player, yes, this is possible. You will need a co-axial (TV) plug for the "Stereo" socket on the record player and at the other end of the cable, a Phono plug. Given the the AU51 was made several years later than the record player, I need to ask others to advise if you will need a standard phono plug or a "long-reach" type? Bear in mnd that your record player is valved and the AU51 is transistorised, they will sound rather different. So you will need to compensate the sound response levels by adjusting the Bass and Treble controls on each unit. As to your query as to the cartrirdge wiring colours, yours are quite standard, the only variation is that what is Yellow on some makes is White on others. It's essential that these are in the correct connection squence.

[ms660]

Originally Posted by Rat-One

Is this always the case?
Thanks
Francesco

So far as I know for those colours on a BSR deck.

Lawrence.

[AndiiT]

Originally Posted by Edward Huggins

....Given the the AU51 was made several years later than the record player, I need to ask others to advise if you will need a standard phono plug ...

The AU51 uses DIN connectors, there are two one marked AMP and the other TAPE. The lead from the Stereo coaxial socket on your needs to connect to pin 3 and 2 of a DIN plug with pin 2 being the screened connection.

The additional amp then becomes the left-hand channel of the stereo pair with the player being the right-hand channel.

As Edward mentions there may be a difference in sound between the player and the additional amp, however I am sure I used a similar set up some years ago, and you would need a very critical ear to notice

Regards

Andrew

[Rat-One]

Dear gentlemen, good morning

Here I come with the good news
Following Lawrence's guidance, I have rewired the tags to the cartridge and now there is sound coming out loud and clear both plugging in the amp and stereo sockets!

I will actually receive the AU51 either today or tomorrow, so I will keep you updated on this one.

One thing I have noticed is that the treble/bass controls do make a difference, although I can say it is a very "subtle" difference.
Is this normal on this player or shall I ask myself(and consequently you all)some questions?

Also for some reason when the autochanger drops the record, the platter slows down quite a bit before gaining speed again.
Normal? Odd? Help!

Thanks in advance!

[Edward Huggins]

The slowing down of the platter during the change cycle on the UA16 shows a lack of torque. This is due to inadequate lubrication, friction and/or idler wheel grip. The lack of variation on the tone controls may be due to failing passive components in the bass and treble circuitry, possible amplifier power loss or a failed Tweeter - as they do in these.

[Rat-One]

Hi Edward
I guess here in the picture is what we need to look at?
Do you suggest I unsolder one end of each element and check values with a multimeter?