Weird fault on Akkord Pinguin K58 battery/mains portable. - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

Steve_P · 12th Mar 2009, 8:48 pm

Don't muck about with that resistor. Change it and check all the wiring. And it is worth changing the diodes - especially the HT one.

Cheers,

Steve P.

Tim · 12th Mar 2009, 10:18 pm

OK Thanks Steve. I'll check over the wiring and pop in a new diode too. Now all I have to do is find a 600 ohm resistor(or two 1k2!!)

MichaelR · 12th Mar 2009, 11:59 pm

Quote:

Originally Posted by kalee20

It does rather sound to me as though the DL96 is being biased 'off', and that there's no DC return path for the grid.

Tim, the fault is exactly as Kalee detailed it was. I would go over the sodlered joints on the resistor with a hot iron and new solder just in case you have a dry or intermittent joint.

Mike

petervk2mlg · 13th Mar 2009, 1:09 am

What about the 2 meg variable resistance in the grid of the DL96? Is this on value?

Peter

Tim · 13th Mar 2009, 7:19 pm

SOLVED!
Would you believe the problem was caued by a bad connection from the tag on the chassis end of the 600 ohm resistor and chassis itself. When I checked the resistor I lifted the non chassis end, and tested across the resistor rather than from the chassis to the free end of the resistor. But how often does a tag problem arise? I only found it by accident, when checking the earth to chassis continuity of the new mains cable(I used the same tag for the mains earth!!)and can only assume it was caused by a corrosive atmosphere from batteries(the tag is quite close to the battery compartment).
An 8ba screw, star washer and nut sorted that one out!!
I also removed the DL96, cleaned the pins and manager to tighten the contacts from the underside of the socket using a handy meter probe. Grid volts now stable and output distortion(well, for MW) free.
All Ok now, with healthy HT of 101 volts.
Thanks again to everyone for pointers and clues.
Is it worth doing a success story?

Steve_P · 13th Mar 2009, 8:00 pm

Yes. That's quite an unusual radio you have there.

Cheers,

Steve P.

batterymaker1 · 13th Mar 2009, 8:10 pm

Quote:

Originally Posted by Tim

Is it worth doing a success story?

Absolutely!

Now take it one step further, and power it on batteries!

Tim · 15th Mar 2009, 12:30 am

Quote:

Yes. That's quite an unusual radio you have there.

Yes Steve, an unusual but none the less clever design. Performs very well on SW BTW(3 SW bands-all with internal ferrite rod or telescopic aerial.)

Looks odd too. It's covered in some sort of faux reptile skin(and those Faux reptiles are a b*** to catch!). Perhaps I will post some pics of it.

Quote:

Now take it one step further, and power it on batteries!

I might, once I've finished licking my wounds! Boy, will I be glad to give this one back!
This one seems to use a 100 volt HT battery and two x 1.5 volts.

Georg SC

Quote:

What is in Your set, where the schematic shows that
"Stabi St35"? If it is a selenium rectifier, think about
replacing it.

It's a pale blue square thing about 6mm thick and 15mm square with two terminals.

12th Mar 2009, 8:48 pm	#21
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: Weird fault on Akkord Pinguin K58 battery/mains portable. Don't muck about with that resistor. Change it and check all the wiring. And it is worth changing the diodes - especially the HT one. Cheers, Steve P. __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?

12th Mar 2009, 10:18 pm	#22
Tim Dekatron Join Date: Jan 2003 Location: Bradford on Avon, Wiltshire, UK. Posts: 3,310	Re: Weird fault on Akkord Pinguin K58 battery/mains portable. OK Thanks Steve. I'll check over the wiring and pop in a new diode too. Now all I have to do is find a 600 ohm resistor(or two 1k2!!) __________________ "Nothing is as dangerous as being too modern;one is apt to grow old fashioned quite suddenly."

13th Mar 2009, 1:09 am	#24
petervk2mlg Heptode Join Date: Jan 2007 Location: Parkes, NSW Australia Posts: 877	Re: Weird fault on Akkord Pinguin K58 battery/mains portable. What about the 2 meg variable resistance in the grid of the DL96? Is this on value? Peter

13th Mar 2009, 7:19 pm	#25
Tim Dekatron Join Date: Jan 2003 Location: Bradford on Avon, Wiltshire, UK. Posts: 3,310	Re: Weird fault on Akkord Pinguin K58 battery/mains portable. SOLVED! Would you believe the problem was caued by a bad connection from the tag on the chassis end of the 600 ohm resistor and chassis itself. When I checked the resistor I lifted the non chassis end, and tested across the resistor rather than from the chassis to the free end of the resistor. But how often does a tag problem arise? I only found it by accident, when checking the earth to chassis continuity of the new mains cable(I used the same tag for the mains earth!!)and can only assume it was caused by a corrosive atmosphere from batteries(the tag is quite close to the battery compartment). An 8ba screw, star washer and nut sorted that one out!! I also removed the DL96, cleaned the pins and manager to tighten the contacts from the underside of the socket using a handy meter probe. Grid volts now stable and output distortion(well, for MW) free. All Ok now, with healthy HT of 101 volts. Thanks again to everyone for pointers and clues. Is it worth doing a success story? __________________ "Nothing is as dangerous as being too modern;one is apt to grow old fashioned quite suddenly." Last edited by Tim; 13th Mar 2009 at 7:33 pm.

13th Mar 2009, 8:00 pm	#26
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: Weird fault on Akkord Pinguin K58 battery/mains portable. Yes. That's quite an unusual radio you have there. Cheers, Steve P. __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?