Blaupunkt Arkansas 58. Turntable not working.

[Redgate23]

Thanks for all your comments, if a new cartridge is needed, is it easy to source and which model would you recommend? Thanks

[Edward Huggins]

The Collaro RC456 autochanger in your Radiogram suggests this comes from late 1956 or 1957. This is pre-stereo. I suspect that your Arkansas is a mono only radiogram. That means there will be only 2 wires connecting the existing Collaro Studio "O" cartridge in the tone arm. If you do need a new cartridge you will need to source a BSR X5M mono, stereo-compatible, cartridge. These are not an easy fit to the tone arm. This also assumes that the records, especially your LPs, that you plan to use on this will be stereo. And I susoect that most of them will be stereo pressings. There is much more to all of this than you may think!

[Station X]

As far as I can see we've not yet established that a new cartridge is definitely needed. If the amp buzzes/hums with the PU leads connected, then there's a problem which may be nothing to do with the cartridge.

To the OP.

Does the buzz persist with the PU lead unplugged?

If not do you get a buzz when you touch the metal part of the PU sockets with a screwdriver blade?

Does reversing the plugs at the PU socket make any difference?

[Redgate23]

Hi Graham, yes there is a hum/buzz when the PU leads are connected (black then red)and the PU button is pressed down, this gets louder when the volume is turned up.When the leads are unplugged there is still a very faint hum/buzz but no where near as prominent as to when they are plugged in. We have touched the metal part of the P U sockets with a metal screwdriver and there is no noise, only the faint hum. We have switched over the sockets, red then black and there is only the faint hum as before.

[Station X]

It's best if you touch the screwdriver blade whilst the blade itself touches the metal part of each PU socket in turn. If you're not doing this, then that could be why the hum/buzz level is low.

[Redgate23]

Hi, we have tried this and there is no hum when we touch the blade of the screwdriver whilst it is touching the metal PU socket. The hum gets louder if we lightly touch anywhere on turntable when the PU sockets are are connected either way round. We have found that the first connection point which is next to the circle with a solid dot inside makes a connection noise when either points are connected, the second connection point does not make any sound when either connectors are placed in.

[Redgate23]

Originally Posted by Edward Huggins

The Collaro RC456 autochanger in your Radiogram suggests this comes from late 1956 or 1957. This is pre-stereo. I suspect that your Arkansas is a mono only radiogram. That means there will be only 2 wires connecting the existing Collaro Studio "O" cartridge in the tone arm. If you do need a new cartridge you will need to source a BSR X5M mono, stereo-compatible, cartridge. These are not an easy fit to the tone arm. This also assumes that the records, especially your LPs, that you plan to use on this will be stereo. And I susoect that most of them will be stereo pressings. There is much more to all of this than you may think!

Hi Edward,

Thanks for your advice on my previous posts regarding the sound only coming from the stylus not the speakers. We are looking to source a new cartridge and stylus as the one we have is bent. We have found a cartridge and just wanted your opinion if this would be the correct one and which model of stylus do you think we need. Many’s thanks.

[Station X]

Originally Posted by Redgate23

Hi, we have tried this and there is no hum when we touch the blade of the screwdriver whilst it is touching the metal PU socket.

Sorry, but this does not make sense to me, as everything else points to a working amplifier.

Perhaps a more knowledgeable forum member can advise?

['LIVEWIRE?']

I'm a little puzzled by 'there is no hum when we touch the screwdriver blade' comment, too. Of course a quick check with an AF signal generator or signal injector should prove the point, but obviously the OP does not have such things. In the meantime, provided the X5M Cartridge will physically fit the Collaro and an 'M' type cartridge is of sufficient output to drive the Arkansas' amplifier, I'd say it would be suitable. B.T.W., has the OP checked whether any sound is heard by gently stroking the tip of the stylus with the volume turned up? If not, this should be done, as it would confirm whether or not the cartridge is faulty.

[Station X]

We're told that the radio works, so any problems with the PU sockets not working must be "internal" to the main unit.

I haven't been able to find a circuit diagram for the 58 model, but at I've looked at that for the 57, which is probably similar. The PU arrangement is conventional with the PU socket being connected to the control grid of the AF valve via the PU selection switch.

All I can suggest is cleaning ALL the switch contacts with Servisol 10 or similar.

Externally, are the wires and cable from the cartridge to the PU plugs undamaged ie no open or short-circuits?

[Redgate23]

Hi, there is no sound when touching the tip of the stylus with the volume turned up.

[Audio1950]

The cartridge you have shown has no mounting bracket, so will be of no use. There is a single screw fixing in the top of the cartridge, but by using this method, the cartridge will not reach the base of the headshell. I also think the cartridge will be too wide for the very small Collaro headshell.

[Edward Huggins]

Noting the OP's Post#27, the BSR X5M is electrically (and it terms of 2 wire connectivity) the most ideal cartridge to use. Possibly it might just fit, BUT there are liable to be issues of just how well it does fit the narrow Collaro RC456 tone arm head, as these were designed to be used only with the Collaro "Studio" series of cartridges.
It might be that the cartridge holder (if supplied) will need to be trimmed in width and the edges of the headshell trimmed away with a Stanley knife.
Given such changes to the original surrounding supporting structures, the cartridge will need to be fitted and aligned with extreme accuracy. I could do this, but I'm 180 miles from Stockport! It might be that a local Member of this Forum may be called on to assist if the OP is not confident.

['LIVEWIRE?']

I didn't think about the mounting bracket, though I may have one somewhere, but if an X5 cartridge is too wide for the Collaro head, the only alternative of which I know is the Chinese 'cheapies*' regularly listed on eBay and elsewhere. As those are ceramic, their output, about 250mV, IIRC, may not be adequate. They are stereo so the two channels would have to be combined (paralleled) for use in a mono player such as the Arkansas. *They sell for about £10 c/w a mounting bracket.

[Redgate23]

Hi, we’ve established that a wire was out of the head, the red was connected. We’ve reconnected the blue so now both wires are in but they don’t seem to have any of metal wire showing through the plastic casing to connect to the cartridge, is it worth exposing some of the metal wire and reconnecting.

[Station X]

It is essential that the conductive core of the wire contacts the pin of the cartridge.

Don't whatever you do solder directly to the cartridge. You'll destroy it. Remove the socket first and solder to that.

[Redgate23]

There doesn’t seem to be any exposed wire, it’s all encased in the plastic coloured casings. Would you recommend cutting back the plastic to expose more wire. Does it need to be soldered or can it just be placed securely inside the black rubber connectors?

[Edward Huggins]

It must be soldered to the connectors - a push fit will totally inadequate. Note that the screened wire sheathing (that surrounds the 2 very fine conducting wires to the cartridge) carries no signal and should be connected under the cartridge holder so that the small screw holds it securely in the head. I'm beginning to wonder if you have been trying to connect to that screened cable thinking it was a conductor? From your photo it looks as if it's connected to one of the signal leads.....Ahh, it's all so very frustrating writing these texts as it would be so very easy for me to sort out if only I was there!

[Station X]

Originally Posted by Redgate23

There doesn’t seem to be any exposed wire, it’s all encased in the plastic coloured casings. Would you recommend cutting back the plastic to expose more wire. Does it need to be soldered or can it just be placed securely inside the black rubber connectors?

You will have to remove a short length of the wire's plastic insulation to expose the copper conductor. This will need soldering to the connector. The black insulating sleeves will not grip the wire tightly enough to ensure a good electrical connection.

[Techman]

Originally Posted by Audio1950

The cartridge you have shown has no mounting bracket, so will be of no use.

The one shown actually does have a mounting bracket fixed to it. It's metal on these and I can also see the optional spacer above it with a screw going through both