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-   -   Capacitors for Trio 9R 59D (https://www.vintage-radio.net/forum/showthread.php?t=153799)

Humptydumpty 7th Feb 2019 11:44 am

Capacitors for Trio 9R 59D
 
I would like to replace some, but eventualy all of the capacitors in my receiver .
I know what value they are but not the wv
The capacitors in question are 0.01 uf + or - 10 % i need 9 .
Question is would they all be 600 wv ? . Need to know just what to order No voltage in manual schematic everything but the voltage is in there .
I have two of these receivers , and the one has a capacitor missing from the function switch [on and off freq selector ] and i would like to replace that one as well . Thank you for looking .

G8HQP Dave 7th Feb 2019 11:50 am

Re: Capacitors for Trio 9R 59D
 
No need to replace all the capacitors; in fact there are good reasons not to change capacitors in RF circuits unless they are definitely faulty. Just change the ones which are faulty and the ones which are likely to become faulty.

Show us a picture of the capacitor, and someone will tell you whether it is likely to cause trouble in the future.

No need for 600V capacitors. Anything above 300V should be fine.

raditechman 7th Feb 2019 12:05 pm

Re: Capacitors for Trio 9R 59D
 
You do not need to replace all the capacitors and may make yourself problems in doing so especially in the RF stages.
The Trio 9R59D was an entry level receiver at budget price when it was sold in the 1970's.
I had one from new back in those days. They always suffered from tuning drift. Hum would be heard if using a decent speaker or headphones, use a speaker with poor bass response and you will not hear the hum. Remember it is a radio for communications not quality broadcast.
For nostalgia I purchased an 9R59D two years ago it worked as expected.
The only modifications I have made are to replace the filament dial lamps with LED's and add one to the S meter. (Fully reversible mods.) I did this to reduce the current load on the mains transformer.
I also added an HT fuse.
I used it this week and still going fine.

John

Station X 7th Feb 2019 12:37 pm

Re: Capacitors for Trio 9R 59D
 
The only non-electrolytic capacitor known to fail in these receivers is C34, the audio coupling capacitor, which I know for a fact you've changed in one of your receivers. It's also been explained to you how to test this capacitor by checking that there's no positive voltage on the control grid of the audio output valve.

Only replace the electrolytic smoothing capacitors if they're leaking electrolyte, get hot, or there's excessive mains hum.

Techman 7th Feb 2019 1:12 pm

Re: Capacitors for Trio 9R 59D
 
Absolutely! You don't need to change ANY capacitors other than the one mentioned above.

If you go round swapping out capacitors for no good reason then you'll ruin it.

You'll need special test gear to conduct a full alignment of the RF circuits if you replace all the capacitors in the set.

I've got an old valve Trio which is the model before yours and it's happily running on all its original capacitors without any problems whatsoever.

Humptydumpty 7th Feb 2019 1:48 pm

Re: Capacitors for Trio 9R 59D
 
Dave - John - Graham . Right i will let sleeping dogs lie as they say .

But i need to fit one on to the function switch of the first Trio i purchased.
Looking inside both receivers you notice things that one set has ,and that the other one has not. Like the base plate is fitted with only 6 screws the other one has 8 .
Trio did things to cut down on the price . And there are more capacitors in the old set . Maybe its why it hums a little but its a 90% better than when i had it .They both are . Also inside on the chassis,there is this tag board that one of the the potentiomiter audio wires are solderd to ,that too has a capacitor ,But the other receiver cap is missing. The first Trio serial no has 3 numbers ,the last one 7 fig serial number. So i do need 2 to start with , to fit in the places i said that the cap is missing

Station X 7th Feb 2019 1:57 pm

Re: Capacitors for Trio 9R 59D
 
As far as I know there are no major differences between the 9R-59D, 9R-59DE and 9R-59DS sets.

Some versions were fitted with a socket wired for a voltage stabilizer. Others just had a hole in the chassis where you could fit your own valve holder and wire it up.

Which capacitor on the function switch needs changing and why?

Humptydumpty 7th Feb 2019 2:35 pm

Re: Capacitors for Trio 9R 59D
 
Well Graham i can see places void of a capacitor in 2 places i mentioned before . The one on the function switch is missing and the one on the tag board that the shielded audio wire is soldered on to on the pcb for the potentiomiter in the bottom of the set .When i replaced the pot yesterday to set no2 i noticed the cap it was missing from the tag in other set .Would pictures help more ?

Humptydumpty 7th Feb 2019 3:04 pm

Re: Capacitors for Trio 9R 59D
 
I checked the location on the function switch capacitor , i did this on both receivers ,and the cap is tucked down the back i never saw it . The capacitor is fitted fom the function switch to the tag board tthat the pot audio wire is attached to . So after all they are indeed exactly the same and nothing missing.

HamishBoxer 7th Feb 2019 6:56 pm

Re: Capacitors for Trio 9R 59D
 
CCCD only causes problems! (Compulsive Capacitor Changing Disorder) Also it is Not fault finding.

deliverance 7th Feb 2019 8:43 pm

Re: Capacitors for Trio 9R 59D
 
Quote:

Originally Posted by HamishBoxer (Post 1118339)
CCCD only causes problems! (Compulsive Capacitor Changing Disorder) Also it is Not fault finding.

Absolutely I learned that lesson the hard way .

Humptydumpty 7th Feb 2019 9:12 pm

Re: Capacitors for Trio 9R 59D
 
Thanks now i know i will leave these caps alone .

Humptydumpty 8th Feb 2019 12:05 pm

Re: Capacitors for Trio 9R 59D
 
Talking about caps . The one Trio 9R 59D as been sorted out with three 47uf 450 volt caps in place of C40- 41 - 42 .
I do need to replace three in my other Trio now .
First set i fitted were axial type and i found them not to hard to fit .. But wished i had purchased radial type after . Can i ask please if someone thats well up on these Trio capacitors check this listing on Ebay and let me know if they are the type i need .Ebay number is 111587915792. Thanks in advance

HamishBoxer 8th Feb 2019 12:11 pm

Re: Capacitors for Trio 9R 59D
 
They look good spec to me.Top quality maker.

David G4EBT 8th Feb 2019 2:41 pm

Re: Capacitors for Trio 9R 59D
 
5 Attachment(s)
You can't really do better than the miniature radial Rubycon ones that I mention at post #118 in your earlier (now closed) thread.

https://www.vintage-radio.net/forum/...=152795&page=6

I wrote:

Suitable miniature Rubycon capacitors can be obtained from Farnell.

47uF 400V rated ones are only 12.5mm diam x 30mm tall.

They're 105 degrees rated, have a more than adequate ripple rating and long life, with a stated life of 7,000 - 12,000Hrs. They'd easily fit permanently under the chassis, but you should of course insulate the positive leads where they join the existing red wires, and the caps mustn't be left just dangling. (They would also fit inside the can).

https://uk.farnell.com/rubycon/400tx...831328?st=47uF Rubycon capacitors

The datasheet of this range of capacitors is here:

http://www.farnell.com/datasheets/23...025.1497772082

End quote.

A pic of a selection that I've used is attached, with can types shown for size comparison.

I invariably re-stuff cans, especially when there's no space beneath the chassis. The pics below are of a re-stuffed twin can on a Unitra Figaro Special - a compact receiver with no space to spare beneath the chassis. The can was 30mm diameter and two caps fitted side by side, but could have been stacked above each other. I'd not suggesting that you attempt to do that on your set, which has plenty of space beneath the chassis to accommodate the three new capacitors.

Have fun.

Humptydumpty 8th Feb 2019 2:53 pm

Re: Capacitors for Trio 9R 59D
 
Thank you Hamish , Anyone else have the same view on these capacitors before i go and order them .

Humptydumpty 8th Feb 2019 3:07 pm

Re: Capacitors for Trio 9R 59D
 
David Thank you for your picture line up . The Furnell link did not work for me .
But as i have found these on ebay i can get them cheaper from there .
Furnell is fine but they sting you with postage . I had my first pot fron them ,cost was £2.25 and £6.88 to pack and post cost £10.49 Can you check them also on ebay David i would like a second opinion.

David G4EBT 8th Feb 2019 3:31 pm

Re: Capacitors for Trio 9R 59D
 
Those caps from the e-bay listing will be fine.

They're Rubycon brand, similar to the ones supplied by Farnell.

They're only 10mm x 45mm, and the ripple rating is 440 mA - way beyond the HT current drawn by the set, so you're sorted.

Don't know what went wrong with the links - they didn't work for me either when I just tried them, but these should work:

https://uk.farnell.com/rubycon/400tx...831328?st=47uF

http://www.farnell.com/datasheets/23...025.1497772082

Humptydumpty 8th Feb 2019 3:52 pm

Re: Capacitors for Trio 9R 59D
 
David yes those are the same ones in your link at Furnell , I will go and purchase them now. Thank you to David and Hamish for your help.

Humptydumpty 8th Feb 2019 4:48 pm

Re: Capacitors for Trio 9R 59D
 
David . After i checked Furnell the price was the cheapest of the two .
So i purchased from Furnell . From Furnell £10.57 and ebay - was £11.82. I did well with the first three i had from Furnell so its the best i would think, to do the same again. David Will they have negative marked on them or is it the length of the lead i can see that one wire one side is shorter than the other .


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