Akai 1710

[Dorian27]

Hi I have the Also 1710 recorder and the motor capacitor is leaking can any one tell me exactly what capacitor I would need to replace this it has 2.0uf 260wv AC on it I would appreciate any help with this thanks

[julie_m]

Any motor run capacitor of 2 microfarads, rated for 260V AC or higher, will be suitable.

Motor run capacitors are specially designed for the job, being rated for continuous operation and able to withstand the combined effects of self-heating and heat conducted from the nearby motor. They are not polarity-sensitive, as they are used on alternating currents.

[Radio Wrangler]

Be sure it's a motor RUN rated capacitor

People confuse them with motor START capacitors, but those are only intended for momentary use and get switched out once the motor is close to speed.

You can accept a higher voltage rating, but no lower. If you can't find 2.0uF, then you'll probably get away with 1.8 or 2.2 uF

David

[Dorian27]

Can you tell me if this type would do as per photo It is 450v AC 2uf do you think this would be ok please

[julie_m]

If it mentions "motor running" as an application, it probably will be OK.

Even if not, it probably will appear to work OK -- for awhile, at least, but it probably won't last forever.

[Dorian27]

I really don't know what type of capacitor to get .I found that the 0.5uf has also gone .I don't know what replacement to get I am not experienced enough can any one point me in the Wright directions as what exactly is the two I need and where I might find as I would like to get it working again please help

[Uncle Bulgaria]

If you search on this forum for 'Akai 1710 0.5uF', you will find five prior threads detailing problems with this capacitor, and what to do about it.

You appear to have found a replacement already for the 2µF motor run capacitor.

[vidjoman]

CPC list about 50 motor run/start capacitors so you should find something there.

[julie_m]

CPC list two possibilities for the 2µF: https://cpc.farnell.com/w/search?cap...un%20capacitor

They don't have any motor run capacitors at 0.5µF, but you probably could use any old 470nF capacitor rated 400V or better (it's going to have only a quarter as much power going through it as the 2µF one). CPC link: https://cpc.farnell.com/w/c/electron...e=inc-in-stock

I'd recommend the Vishay MKT468; they are the spiritual descendant of the Mullard "tropical fish" capacitors, about which nobody seems ever to have said a bad word .....

[Dorian27]

I can't thank you enough for this I will get these and get my old recorder working again I hope thank you

[julie_m]

It might be worth taping a note inside the machine about the capacitor replacement, just in case the 470nF fails prematurely but not so prematurely that this is still fresh in your mind.

A proper motor run capacitor has separate layers of aluminium foil and poly film, rolled up. A general purpose capacitor has two layers of polyfilm with a metallic coating on one side, rolled up and flattened into an oval. This gives it a higher internal resistance (and a smaller surface area). In a motor running application, there is always a fairly large current flowing through the capacitor, and the power dissipated in this internal resistance means it will get warm. This could cause its value to change, even if it is not enough to melt it completely. But the current through the 470nF capacitor will be smaller that the 2µF one, so there will be less heat.

If you manage to find a 0.5µF / 500nF motor run capacitor (470nF would do and might be a more common value; or even two 1µF in series, if space permits) somewhere else, by all means use that instead. Otherwise, try the Vishay one and see how long it lasts. It's not ideal, but it will certainly outlast any of those cheap no-name capacitors with the brown resin coating.

[Dorian27]

I have ordered a motor run capacitor to replace the 2uf 260wv one the one I ordered is a 2uf 440v it has 2leads a blue and a brown. The original motor leads connected to the old capacitor are yellow on top and red on the bottom which should I connect to red on the new one brown or blue or does it not matter can any one tell me please. I am still having problems trying to get a replacement for the0.5uf 350wv capacitor please help

[Dorian27]

Can you tell me the 0.5uf 350wv AC or dc I can get a 0.5uf 350wv dc would that do

[julie_m]

Generally, if a capacitor only has an AC rating, you can multiply this by the square root of 2 (=1.41421356237) to get the equivalent DC rating. That's because with AC, it's usual not to specify the maximum (peak) voltage reached above or below zero, but the equivalent DC voltage that would produce the same amount of heat in a resistive load; and for a sine wave, that happens to be equal to the peak voltage divided by 1.414.

But note that if a capacitor only has an AC rating, usually it's a special type of capacitor and shouldn't just be replaced with any old general purpose one .....

The Vishay 470nF capacitor may well be fine. If you have a temperature meter with an external probe, you could easily monitor how hot the capacitor is getting.

[ms660]

If you only intend to use the machine on 50Hz mains, cut out and throw away the 0.5uf capacitor and fit a 2.5uF motor run capacitor in place of the 2uF capacitor, and make sure the mains frequency selector switch is set to 50Hz.

If you look at the schematic you will see that pins 3 & 4 of plug and socket J4 & P4 are connected together when 50Hz mains is selected, that connects the 2uF and the 0.5uF capacitors in parallel, when capacitors are connected in parallel their capacitance values are simply added together...So, 2uF + 0.5uf equals 2.5uF...

Lawrence.

[Dorian27]

Sorry to be a pain but when you say cut out the capacitor just throw it away does any of the wiring have to be changed at all if this is done I do only want it on 50HZ that would do me fine

[ms660]

You don't have to change the wiring, just remove the 0.5uf capacitor and the 2uF capacitor and fit a replacement 2.5uF capacitor where the 2uF capacitor was and connect it to where the 2uF capacitor was connected to.

Lawrence.

[Dorian27]

Thank you Lawrence very much I am most grateful to you

[julie_m]

If you're never going to go anywhere with 60 cycles mains, then 2.5µF seems to be a reasonably common value: Google Search Link. Make sure to choose a motor run capacitor, not a motor start capacitor; the latter are not intended for continuous operation. Just wire the new capacitor exactly where the 2µF used to go, and remove both the old capacitors. Make safe by unsoldering or cutting short any wires no longer needed The frequency switch will have no effect anymore (all it does is connect the 0.5µF in parallel with the 2.0µF when set to 50; by replacing the 2.0 with 2.5µF, it's equivalent to being on 50 all the time).

[ms660]

The mains frequency selector switch also alters the voltage that powers the motor so far as I can make out, so make sure it's still set to 50Hz.

Lawrence.