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  Kriesler 11-104 refurbishment
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 Return to top of page · Post #: 1 · Written at 8:54:42 AM on 11 October 2023.
Feral's Gravatar
 Location: Newcacastle, NSW
 Member since 14 October 2017
 Member #: 2175
 Postcount: 10

Hey All,
I hope to start refurbishing my Kriesler 11-104 soon.
Can anyone suggest a good place to start?
What type of capacitors should the old ones be replaced with?
Any traps I should look out for?
I live near Newcastle, is there any places around that might be a good place for advice if needed.
Cheers
Ken


 
 Return to top of page · Post #: 2 · Written at 9:15:41 AM on 11 October 2023.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5303

Find its data perhaps Kevin Chant, if its not with it: Remove the chassis so it can be worked on and inspected. Then photograph it underneath so we can see what really is in it.


 
 Return to top of page · Post #: 3 · Written at 2:18:01 PM on 11 October 2023.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6720

Schematic is available here: https://www.kevinchant.com/uploads/7/1/0/8/7108231/11-98a11-104_11-109_11-114.pdf

Can anyone suggest a good place to start?

Checking voltages against the schematic, however ...

How long since this set was last powered on? If quite a while DO NOT power it up without first checking for the usual faults which may cause irreparable and otherwise avoidable damage if power is applied beforehand.

What type of capacitors should the old ones be replaced with?

General rule: replace like values with like values. Higher capacitance is OK if necessary. NEVER go lower with working voltage -- use same or higher. Be careful to get polarity correct with electrolytics.

Any traps I should look out for?

The first one is getting shocked or killed by high voltage. If you are not completely familiar with the safety rules for working around high voltage then don't attempt to. Period.

Going by your questions I suggest that you need help with this.

I live near Newcastle, is there any places around that might be a good place for advice if needed.

Suggest that you join the HRSA Central Coast Group. Contact Wal Peters tetrode.bigpond.com


 
 Return to top of page · Post #: 4 · Written at 8:21:02 PM on 11 October 2023.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2405

Your 11-104 is probably too new to need re-capping. By this time Kriesler were using polyester caps (which you never need to replace) and Ducon electrolytics. These are good quality and normally still OK.

Mica caps in certain positions can give trouble though. If you get intermittent crackles it may be due to Silver Mica Disease.

I suggest you bring it up using a Dim Bulb (google it) just in case.

It may have faults (such as scratchy control pots) but replacing caps will not fix it.

My email is unhidden and I'm in Sydney. Send me a clear pic of the underside of the chassis and I'll be able to advise you better.


 
 Return to top of page · Post #: 5 · Written at 3:37:47 PM on 14 February 2024.
Feral's Gravatar
 Location: Newcacastle, NSW
 Member since 14 October 2017
 Member #: 2175
 Postcount: 10

Thanks Ian,
You are right, The caps look pretty good to me.
Photo to follow.
The thing now is that when I try to play a record, there is basically no sound. with the volume turned right up I can just hear the music.
The radio is working but scratchy and noisy.
Thanks Again

Kriesler 11-104 valve radio


 
 Return to top of page · Post #: 6 · Written at 6:48:55 PM on 14 February 2024.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2405

Sounds like the record player cartridge might need replacement, they usually do by this age.

WES components has a good range. You need a CERAMIC cartridge.

But you can check this first by switching to gram, turning the volume to max and touching the terminals at the back of the cartridge (under the arm) with a metal screwdriver held with your fingers. You should get a loud "burp" through each speaker, depending on which terminal you touch. (it is quite safe to do this!).

If you do, the amplifiers are OK.

How is AM radio reception normally where you live? There is a lot of interference around these days from LED lighting inverters and solar power systems. You may need a properly-installed outdoor antenna. The internal antenna is directional, you may just need to rotate the unit a bit to null out the interference.

If it makes crackling noises when you tune across the dial, the rotor grounding spring may need cleaning. Easy to do.

Email me, I can give you my phone number and I can talk you through your project. That model Kriesler was basic but very reliable. I doubt there will be much wrong with it.


 
 Return to top of page · Post #: 7 · Written at 5:18:24 AM on 15 February 2024.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7342

Photo uploaded to Post 5.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 8 · Written at 7:52:12 AM on 15 February 2024.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2039

I see some wax caps there. In my opinion they should be replaced.


 
 Return to top of page · Post #: 9 · Written at 8:42:21 AM on 15 February 2024.
Johnny's avatar
 Location: Hobart, TAS
 Member since 31 July 2016
 Member #: 1959
 Postcount: 558

Yes, needs a bit of work.
Burnt up 2 watt resistor in power supply.
Wax paper capacitors need replacing.
Looks like leaking/spewed cathode bypass electrolytic cap.
And there possibly are a few out of tolerance resistors.
Clean/tighten valve sockets.
JJ


 
 Return to top of page · Post #: 10 · Written at 10:40:45 AM on 15 February 2024.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5303

Wax paper caps and oil filled types should be replaced on sight. Those caramel polyester caps are normally reliable but I have seen some crack their jackets.

The Elna caps are quite good but any electrolytic with chemical oozing out of it is a dud. You just don't replace power filter caps, they all die the same way. They are chemical & will lose form (polarity) if left for an extended period. The ramifications of that are that they may present as a short circuit, or major over load. That can, and has, caused burnt out rectifiers & transformers.

I normally check resistors as best as, as I change caps, in the older sets, that increases the probability of not having to do rework and it running. As noted previously non-polarised caps need two tests; Viz capacity and leakage at working volts. If it leaks its a dud.

Electrolytics are meant to leak, but there is a limit. I have reached to point where I will put them on a reformer before I use them. One should check for the obvious before even thinking about power. If there are burnt parts & oozing electrolytics and bare deteriorated wire, you do not power it.

The reformer I built is capable of powering a HT in a radio with the heaters off. If there is no voltage divider (that can be disconnected) you can power the HT for the purpose of pinging bad (new) HT caps and shorts (it will lock up on short).

I have seen one 563MA on Internet and one on my bench where a globe socket has shorted. Net one overheated the transformer badly & the fixer only burnt the wire.


 
 Return to top of page · Post #: 11 · Written at 12:35:18 PM on 15 February 2024.
Feral's Gravatar
 Location: Newcacastle, NSW
 Member since 14 October 2017
 Member #: 2175
 Postcount: 10

Thanks all,
I can see the leaking one now. It's a the large paper one at the top.
What type of caps can I replace them with? Do I just go to jaycar and ask.
It has been 30 plus years since I seriously read a circuit diagram and I am definitely having trouble.
I don't suppose some has a circuit layout somewhere? To help identify parts.

By my calculations the burnt out resistor is R30 220.

I am getting no feedback through the speakers when I touch the terminals of the cartridge. Does that mean the amplifier is shot?
Thanks again


 
 Return to top of page · Post #: 12 · Written at 7:40:35 PM on 15 February 2024.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2405

Service manual was posted by GTC on the 11th of October.

To find your way around the circuit start with the valve pin numbers. You'll find it's easy to trace you way around this way.

I will get back to you with what parts should be replaced and where you can get them. A couple of those paper caps have high voltage ratings. Not so easy to find.

Elna electros, and most of the caps are good.


 
 Return to top of page · Post #: 13 · Written at 9:27:57 PM on 15 February 2024.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5303

The common non-polarised cap for them is now is 630VDC. The cap if on the plate of the output tube is often in the order of one to 2KV. I envisage that it is only those wax paper ones that need replacing.

A burnt resistor says problem. To speculate on it one needs a circuit.


 
 Return to top of page · Post #: 14 · Written at 8:03:50 PM on 16 February 2024.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2405

OK, Ken.

I'll send Brad a picture showing the parts that will need to be replaced and one resistor that should be checked.
Email me and you'll get it quicker that way.

For the post-mortem, you should first check the resistance of R25. It is a type that goes LOW resistance when it is stressed. Bad!

R30, being twice the resistance, is effectively in series with the B+ load, as is R25. So all things being equal you would expect them both to be equally charred, but they are plainly not.

So, either C32 is open circuit (adding ripple current to R30) or R30 has gone high.

Measure R30. You can measure both R30 and R25 in circuit, no need to cut them out.

If they both measure correctly within 10% then C32 is suspect.

I think you will find R30 will measure high.

Why did this happen?

C25 and C26 are not suspect (although you should replace them anyway) because, if they were leaky, you would see signs of distress on either or both 5.6k resistors R22 and R23. I don't see that.

I suspect C28, because, it it were leaky (and it probably is) that would shunt the bias away from the two output valves and cause them to pull too much current, hence stressing R30 and R25.

While you are at it, change C8 up the other end. It's probably not too bad because I see no signs of heating of R28, but, hey, it's a paper cap and it's only a matter of time.

C25 and 26. Hard to find high voltage caps these days.

https://au.element14.com/

Part number 2469019 or 2495756

Jaycar has the other parts:

R30 RR3282 (this is a more rugged 5 watt part!)
C8 and C28 RG5205

For the cartridge, this one should do:

https://www.wagneronline.com.au/ceramic-cartridge-stereo/cartridge/turntable-parts/service-repair-parts/pc20-75034/999484/pd/

Kriesler 11-104 chassis


 
 Return to top of page · Post #: 15 · Written at 10:31:36 PM on 16 February 2024.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5303

I would disagree on the caps being hard to get I have bought in stock this month. I carry stock as I repair.

I normally use one watt from Jaycar to get the voltage rating that is rarely published these days. Higher wattage resistors are gettable.

If the thing is back biased, heavying up those resistors is suicide. Better they burn than the rectifier or transformer on overload.


 
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