Ekco RP364

[DonaldStott]

Despite the fact that my ToDo pile has increased significantly due to months of inactivity on my part I managed to pick up this Ekco RP364 for next to nothing at a local Auction. What attracted me, apart from the cost, was the fact that it has a stereo amplifier, a second speaker in the lid to facilitate stereo reproduction (or so I thought!) and a Garrard RC209 auto-changer.

1. Initial assessment - The record player seems to be in very good condition externally with no obvious defects. All control knobs, badges and trim are present and the Garrard auto-changer looked to have all its various components and switches. Tried an initial power up using my lamp limiter which cycled correctly through valve warm up but I have the ubiquitous 50Hz hum at all volumes! Tried injecting a 1kHz signal to the wiper of the volume control and although a tone is heard from the speaker it wasn't clean to my 'audiophool' ears. Looking at the output signal on my 'scope I have this which I think is the 50Hz hum superimposed on the 1kHz injected signal:-



2. Garrard RC209 - Although the Ekco RP364 is configured for stereo reproduction i.e. stereo amp and second speaker, the Garrard auto-changer is only wired for mono - there is only a single connection to the cartridge with a brown and black wire? In addition the stylus appears to be 'wrecked' probably due to the tonearm not being locked down while transporting? There also appears to be 'green goo' leaking from the cartridge: -



Both the stylus and cartridge will need to be replaced and the whole auto-changer rewired for stereo reproduction - recommendations please?

3. Auto-changer - As expected the auto-changer doesn't function while removing the platter and looking at the mechanism underneath revealed that common problem of a white coating on all metal parts: -



I can't remember which metal these parts are made from so any advice on this along with cleaning recommendations would be greatly appreciated? In the above image I've circled in RED a bearing where the nut and washer have gone missing but easy to replace. I've previous experience of restoring a Garrard RC10 so this doesn't appear much different apart from the fact that the RC209 doesn't have a detachable tone arm head shell. Not sure how to remove the existing cartridge?


That's the probably enough to be going on with but more detailed questions will no doubt follow - thanks in advance!

[Nickthedentist]

Hello Donald,

(2) Very odd! It should of course have a stereo cartridge and wiring. Don't worry about the stylus being damaged, because the cartridge has had it, evidenced by the green goo. It will need replacing.

(3) Clean with any standard solvent, e.g. meths, isopropyl alcohol.

[DonaldStott]

Thanks Nick - very odd indeed?

Here is the second speaker installed in the lid:-



And this is the loudspeaker control ‘switch’ :-



I tried some IPA on the white deposit but not much success:-



Ideally I’d like a stereo flip over cartridge (LP/78) so any recommendations?

[DonaldStott]

A quick update and some good news - I didn't look closely enough at the wiring to the cartridge and failed to notice that they are in fact very small co-axial screened cables:-



The cartridge is marked ACOStereo 73 - a make I've never heard of but a bit research shows that the ACOStereo ceramic cartridge was a component of stereo audio systems in the 1960s.

This one certainly needs to be replaced with a modern equivalent?

[Nuvistor]

Looking at the circuit it has a bridge full wave rectifier, if the hum is 50hz then one leg of the bridge is O/C, 100hz check the reservoir/smoothing.

[DonaldStott]

Originally Posted by Nuvistor

Looking at the circuit it has a bridge full wave rectifier , if the hum is 50hz then one leg of the bridge is O/C, 100hz check the reservoir/smoothing.

Thanks I noticed that as well so couldn’t understand the 50Hz hum I reported - turns out I really need to think about investing in a modern digital oscilloscope as my ability to accurately count on-screen divisions and calculate frequency is lacking!

Using a simple SmartPhone frequency analyser app I can clearly see that the hum is indeed 100Hz so the reservoir/smoothing caps are likely culprits.

[Edward Huggins]

The AcosStereo 73 was widely used in this early 1960s period, even though it may not be familiar to you. Fit a BSR SC11M or a BSR SC12H - or with a bit of fettling, the ubiquitous "Chinese Red Stereo" generic cartridge.

[smiler411]

There is a flip over version of those Chinese cartridges, I have used them and they seem to work fine and the cost is so low there is nothing to loose trying one really. You can find them on ebay, aliexpress etc. You will probably need to make some way of mounting them but this can be done fairly easily

[DonaldStott]

Thanks smiler411 and Edward - I’ve ordered up a couple of those cheap flip-over cartridges and should be able to fettle a mounting from the bits-n-pieces I’ve salvaged from various auto-changers over the years.

[DonaldStott]

The white coating on the metal links is proving to be extremely stubborn even to IPA!

I’m not sure exactly what this is or how it can be removed?

[Nickthedentist]

It’s probably a corrosion product, it may even be toxic. I would be tempted to leave it.

[Gabe001]

Originally Posted by smiler411

There is a flip over version of those Chinese cartridges, I have used them and they seem to work fine and the cost is so low there is nothing to loose trying one really. You can find them on eBay, AliExpress etc. You will probably need to make some way of mounting them but this can be done fairly easily

I have one of those in my black box, replacing an Acos that was incorrect for the player as the output was too high. I have been advised that the 78 end of the stylus is not a real 78 and I've never used it to play 78's. It's fine for standard LP's though. The red version without the flip over stylus is cheaper and performs equally as well. Mounts are available from eBay for a fiver or so

[vidjoman]

I think the white coating is probably corrosion of the plating which was probably zinc. Ordinary cleaning fluids like ISP won’t touch it. Don’t know what is the way to remove it. It was often known as zinc and passivate which usually turns it a gold coloured coating. Usually seen on BSR turntables but I thought that Garrard just used inc plating.

[DonaldStott]

My main concern about the white coating isn’t aesthetics but the fact that it is powdery and may impact on the operation of switches, bearings and linkages?

[Edward Huggins]

Highly unlikely if the coating is firmly bonded to the metal. If not clean it off with white spirit.

[DonaldStott]

Moving on from the white coating on the linkages I've cleaned as much of the old dried grease as I can and applied new grease but the auto-changer is still not fully working?

At the end of playing a record the tonearm lifts and returns to the arm rest but doesn't settle, it simply repeats and goes back to playing the same record?

[Edward Huggins]

Are you using the overarm correctly - is it in-situ as it should be?

[DonaldStott]

Originally Posted by Edward Huggins

Are you using the overarm correctly - is it in-situ as it should be?

Both the Overarm and Record Selector Arm are moving freely and not sticking, so no problems there.

As with almost every Garrard auto-changer I’ve restored the problem is usually the idler wheel and this is after trying most of the so-called ‘fixes’ offered on this Forum and others!

The rubber feels ok but seems to lack the required torque to drive the auto-changer mechanism at the start and end of each record - seems to be a Garrard 'feature'!

[vidjoman]

The idler is probably good as it’s returning the arm to the rest. Check the over arm is triggering the shut off system.

[DonaldStott]

Originally Posted by vidjoman

The idler is probably good as it’s returning the arm to the rest. Check the over arm is triggering the shut off system.

The tonearm does NOT return and settle on the rest as it should while the platter and auto-changer mechanism sticks at the end of a record?