Dansette Junior Tone arm.

[NitmoiZ]

The little plastic peg which retains the balance adjuster spring assembly just gave up. The plastic webbing under the tone arm has no thickness to drill for inserting a metal peg to replace it. Has anyone fixed this problem before?

[NitmoiZ]

Here is a picture of the tone arm.

[Edward Huggins]

I would Araldite (or Bostic Super Glue) a very small, flat topped, bolt into the same location as the peg was. When set, hook the adjuster onto it.

[Audio1950]

A short piece of metal, such as a cut-down nail, fixed into the plastic webbing with a blob of "Plastic padding" will do the job. Before cutting the metal down to size, file a circle round it to hold the end of the spring.

[NitmoiZ]

Thanks for the suggestions Edward and Audio. Pretty much what I was thinking. 2 Pack something involved for sure. I might have to cut out the web where it snapped off. It might melt out with a soldering iron.

I intend to use it for 78s so I am not about to ruin any vinyl records

[NitmoiZ]

Well I sorted it yesterday. Set the weight with a set of tone arm scales but had to up the weight to stop the skating.

I ran it up on a 40s 78 and surprisingly great sound and apart from a bit of a wobble on the deck it was fine.

Next flipped the stylus to LP and tried out the 10" Glen Miller Story LP. This also worked fine.

Chattanooga Choo Choo chuffed along fine until the last reprise then a huge screeching noise pierced my ears! I turned it off no reduction in volume as it was turned down.

Started it again a minute or so later and no noise but it might need to warm up to do that again.

Anyone know what is causing this noise?

[Audio1950]

Is the screeching sound coming from the amplifier, or is a mechanical noise, i.e. from the turntable?

[NitmoiZ]

Hello Audio1950. It is the amplifier, really loud and not affected by the volume control. Stopped when turned off.

[Edward Huggins]

Sounds like the reserviour and smoothing caps have failed - as they do at this age. I think you will need a 32uF and a 16uF, both at 350Volts.

[slidertogrid]

It could also be the amplifier valve gone microphonic. I was going to suggest feedback from the speaker to the pickup but it can't be that if it still does it with the volume turned down.
Are you sure the noise is from the speaker and not the motor? they can screech if the bearings are dry...

[Audio1950]

I know I'm thick, but if the volume is turned down, and screeching can still be heard, how can the noise be coming from the amplifier? Just curious!

[slidertogrid]

Not at all Barry! The amp can still go into oscillation and produce various noises with the volume turned down as the volume control controls the level of signal going into the amp. For example if you were to introduce hum onto the "amplifier end" of the volume control you would get a full volume buzz regardless of the position of the control.
Rich.

[Techman]

It could well be dirty valve pins and base sockets - give them a gentle clean. Very fine sandpaper on the pins and switch cleaner in the sockets.

[Stylo N M]

Hi,

This fault could well be a result of many things, as it hasn't been established as to when the unit was last serviced or checked over.

Are you able to make a few basic checks yourself, have any of the usual suspects regarding components, like capacitors been replaced recently? If not I strongly suggest the unit should not be used until some checks have been made, are you able to do this?

Remember always stay safe, if you are not sure, we will always help you as much as we can, if you want to make some basic checks.

Paul

[NitmoiZ]

It has been standing in original condition in the previous owner's dry loft, unused for around 40 years. I'll clean the pins. It sounded perfect before and again perfect after and it is not the turntable. I greased all grease needing parts and sewing machine oiled all other mechanicals. It runs sweet if a bit wobbly.

[NitmoiZ]

Thanks for all the suggestions. What a wonderful response. I'll see if the caps look dodgy. I can remove and solder but don't understand most testing. I can do resistors

[Stylo N M]

There won't be many resistors in the circuit to test anyway, the best way to test them is to do it with the valve removed, so any resistors that are connected to the valve base will automatically be disconnected from the circuit, by the removal of the valve. Avoid the temptation to try lifting one side of any resistor from the circuit to test it, as the heat from the soldering iron will push the resistance even further out of spec, just test it in circuit, it will measure slightly on the high side in circuit, and is likely to be OK anyway.

There's likely to be a wax paper covered capacitor with a value marked on it somewhere in the reGion of 0.01uF 350 volts or more, i would pay particular attention to it as these waxies as we call them were occasionally troublesome even in the day, and if it isn't leaky now it most certainly soon will be so my advice is to change it regardless. Modern yellow polypropylene replacements are easily available, whatever the value of your capacitor is a replacement of 630 volts or higher is ideal.

As Techman has already suggested, give the valve pins a good clean, check for any loose connections, and clean away any surface dust that may be between the valve pins and valve holder that might be harbouring damp.

There may well be a long silver metal can capacitor, which also may well be housing two capacitors in the one can, it may have a rubber seal at one end, so for now if possible just check to make sure there isn't a bulge in the rubber bung. If the capacitor seal is bulging with a crack in the centre of it, unfortunately it will have to be replaced (two separate capacitors can be used) so we won't go into that at the moment until its condition has been established, and I don't want to go in too deep, and you ending up overwhelmed and not knowing what to do.

I'm not sure if this model is valve rectification, it may not be, it could well be just a one valve amplifier with a small solid state square metal type rectifier, perhaps with a small sealing nut on the top. Again we won't go into the ins and outs of that, until the other avenues that have already been suggested, and the suggestions of other members have been esplored first.

The rectifier, should it be a metal type, isn't just a case of direct replacement with a modern one anyway, it may involve an extra component, a wire wound resistor and if I was doing that myself i to would have to ask for the guidance of other members on here.

Paul

[Techman]

This will just be a very simple single valve, single stage circuit, so there's not likely to be much in the way of capacitors to worry about. A clear photo or two of the amplifier unit will confirm what may need to be replaced, if anything. Measure the HT voltage which should be over 200 volts and then check the anode and screen voltages on the valve (look up the data for the valve on-line) and a visual check for bulges on the bottom of the smoothing can capacitor as has been said in the above post and if all's well, then it's probably just bad valve pin to base contacts.

[Techman]

Looking into this a bit further, it looks like there may have been more than one version of this amplifier. There was a more complex two stage amplifier used in some models of the player, so if yours has this better amplifier fitted, then capacitor trouble could be a real concern. You need to take pictures of the amplifier showing all components and report the valve type number used.

[Edward Huggins]

The Dansette "Junior" used a EL84 in a mains isolated circuit, the "Junior De Luxe" used a UCL83/UY85 2 stage amp and non-isolated.