Hacker Cavalier Loud Noise

[martinpinner]

Hi I am currently restoring a Cavalier GP 15 and have changed capacitors and resistors based on information gained from members and on the forums. I have been trying to get the pick up dropping height and dropping position correct so that the pick up will return to it's rest and switch off. I am using the original Ronette cartridge to do this before I find an alternative replacement. The stylus is not good.Whilst making adjustments the player has made a loud boom noise through the speaker that can only be stopped by switching off.This has happened now on several occasions and even if I remove the cartridge whilst it is making the noise it still continues. Is this related to the cartridge or something else. Any assistance would be appreciated. Thanks Martin

[Nickthedentist]

Could be anything, Martin, but try removing/re-seating the valves a few times before delving deeper (with the mains supply removed, of course).

[martinpinner]

Thanks Nick.

[martinpinner]

I am looking to replace the cartridge in the Cavalier to enable playing of stereo records.It is currently fitted with a Ronette DC-400-SCM but this is not listed as being fitted in the manual. Could you suggest replacements. Thanks Martin

[Nickthedentist]

I would imagine that the ever-faithful BSR SC11m from Maplin would work well in these.

[Audio1950]

Originally Posted by martinpinner

I am looking to replace the cartridge in the Cavalier to enable playing of stereo records.It is currently fitted with a Ronette DC-400-SCM but this is not listed as being fitted in the manual. Could you suggest replacements. Thanks Martin

The "SCM" you refer to suggests "Stereo compatible mono", in which case it will be safe to play stereo records. Having said that, I've never come across a mono Ronette cartridge that is stereo compatible. Are those identifying numbers on the actual cartridge, or the stylus?

[martinpinner]

Thanks. The identifying numbers are from the cartridge.I have re-seated the valves and put some switch cleaner on the holders. They do not seem to be a tight fit. Unfortunately, as soon as I switch it on I get the really loud crackly noise whereas before it was intermittent.

[dseymo1]

Since you've already replaced suspect components, it's most likely to be a dry joint somewhere. Is it sensitive to tapping with a screwdriver handle or similar?

[martinpinner]

I am not sure as I switch off immediately as the noise is really loud and maybe it will blow the speaker.The noise subsides within a few seconds once switched off. Just in case I have missed replacing a component I am listing what I have changed.

Resistors R2/R6/R7(220K)
R9( 1ma)
R11/R12(820k)
R4/R8(2.2K)
R10(10k)
R15(1.5K)

Capacitors C3/C5/C9/C10(50uf)
C8(8uf)
C8(8uf)
I was advised to leave C11/C12(50+50uf)

A dry joint is a poor soldered joint

[martinpinner]

I have looked on line at the BSR SC11M and find that it has four connections whereas I have only two available. Is there a good cartridge with two connections or will I have to modify. Thanks

['LIVEWIRE?']

If the Cavalier has the two 'spare' leads inside the PU Arm, these are connected to one channel of the SC11m, and the existing two leads (Red & Black?) to the other. For mono operation the two channels are paralleled at the tagstrip under the deck, although IIRC, the Cavalier has a switched socket at the rear that parallels the two channels unless the 'add-on' stereo amplifier is connected, when a switch in the Phono socket concerned is activated as the (long reach)phono plug is inserted.

[Edward Huggins]

You will actually find it quite difficult to buy a Mono (just 2 connecting pins at the rear) Stereo-Compatible cartridge now. If you do find one, do ensure that it is Stereo-Compatible - a Mono stylus will damage your Stereo records. The SC11M is a good choice for your Hacker - just bridge the LH and RH channels. Edward

[Michael Maurice]

Its not the easiest job in the world, but remove the amp from the record player.

You will see that the two tag strips at the bottom which hold most of the components are bolted to the chassis by 6BA nuts and boths.

Remove these, lift the tag strips up a little an use some fine emery paper to clean the chassis and the tags.

Now replace the screws and nuts making sure they are tight.

Alternately you could connect each earth tag together with some insulated wire to ensure that they are all connected together.

By the way you can use this cartridge

[Edward Huggins]

This will be helpful to Martin Pinner and many others. I think that these BSR X5Ms are the last now available anywhere in the UK - and that Musonic must soon sell these through! Edward

[martinpinner]

Thanks to everyone for responding. I will order a BSR-X5M cartridge and hopefully be able to resolve the loudness noise immediately it is now switched on.

[Edward Huggins]

The new cartridge (now at £40) will improve the "loudness", but it will not affect any "noise". Edward

[nigelr2000]

You missed the 2 most important to change capacitors, C6 & C7 .05 at 400 volt, they go leaky and cause all sorts of problems some very serious so change on sight, .047 is the modern equivalent value. Don't run it any more until they have been changed. They could even cause the awful noise you are getting

[martinpinner]

Thanks regarding C6 and C7. I have changed these but forgot to put on my list. I found a poor soldered resistor today and put this right and have been working on it for about an hour trying to get the pick up lift and return working correctly and it did not give the loud noise. I then re-checked all the mechanics of the levers and replaced a cartridge lead and went back to adjusting the pick up.It now goes crackly and the loud noise kicks in again.

[Edward Huggins]

Can you describe this "loud noise" better please and is it continuous? Edward

[martinpinner]

It is a little crackly at times and like a surge of full volume. It is continuous and I therefore switch off immediately. Strange that after repairing the solder on the resistor and replacing the cartridge lead it came back. I have looked at the cartridge lead and the solder seems quite close to the other leads connection and will redo this tomorrow - just in case this might be the problem. Thanks Martin