'Frako' Electrolytic Capacitors - UK Vintage Radio Repair and Restoration Discussion Forum

'LIVEWIRE?' · 3rd Jun 2015, 12:17 pm

These were used in Blaupunkt Car Stereos made in the 70s & 80s, and, in a Heidelberg SM21 I've found two to be completely short circuit, one the main smoothing capacitor C2000 (2200uf/16v), and a speaker coupling capacitor C1640 (1000uf). Because, IMHO, it's so rare for Electrolytic Capacitors to fail S/C, I intend to replace all 5 Frako Capacitors in the audio amplifier circuit.
Has anyone else had experience of these capacitors failing s/c?

camallison · 3rd Jun 2015, 12:48 pm

We had some "infant mortalities" with FRAKO electrolytics in the early 70s. IIRC, around 40% failure rate - that was in computer peripherals that we manufactured in Germany and the UK. It turned out to be a "grey" source, possibly rejects finding their way back into the marketplace.

Colin

Nickthedentist · 3rd Jun 2015, 2:17 pm

I've had these go s/c in 1970s Grundig tellies too.

jjl · 3rd Jun 2015, 3:34 pm

I've seen Frako electrolytics in Revox and I think B&O kit. I've never encountered a faulty Frako though.

John

camallison · 3rd Jun 2015, 5:27 pm

They were probably genuine 1st quality ones then.

Colin

tri-comp · 4th Jun 2015, 7:47 am

When I see a 'Frako' cap. it triggers my 'Kill on Sight' gene.

Must be a reason for that...

/tri-comp

'LIVEWIRE?' · 4th Jun 2015, 8:21 am

They were almost always used in Blaupunkt Car radios & Stereos in the 70s & 80s, and no doubt in their domestic audio, etc., too. The only markings on the one I've replaced from the SM21 are on the top '2200/16' 'FRAKO' (in caps!) 'N I' , & '+'. This, and all theothers in the stereo are axial gold coloured types, all of which I will replace. Looks like they, like the 'horrible Hunts', waxies, & Plessey red & yellow Electrolytics, fall into the 'replace on sight' category, but then I guess none of the above were expected to last 40 or 50 years!!

3rd Jun 2015, 12:17 pm	#1
'LIVEWIRE?' Rest in Peace Join Date: Mar 2006 Location: N.W. Oxfordshire(Chipping Norton) Posts: 7,306	'Frako' Electrolytic Capacitors These were used in Blaupunkt Car Stereos made in the 70s & 80s, and, in a Heidelberg SM21 I've found two to be completely short circuit, one the main smoothing capacitor C2000 (2200uf/16v), and a speaker coupling capacitor C1640 (1000uf). Because, IMHO, it's so rare for Electrolytic Capacitors to fail S/C, I intend to replace all 5 Frako Capacitors in the audio amplifier circuit. Has anyone else had experience of these capacitors failing s/c?

3rd Jun 2015, 12:48 pm	#2
camallison Heptode Join Date: Feb 2013 Location: Yarm, North Yorkshire, UK. Posts: 535	Re: 'Frako' Electrolytic Capacitors We had some "infant mortalities" with FRAKO electrolytics in the early 70s. IIRC, around 40% failure rate - that was in computer peripherals that we manufactured in Germany and the UK. It turned out to be a "grey" source, possibly rejects finding their way back into the marketplace. Colin

3rd Jun 2015, 2:17 pm	#3
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,861	Re: 'Frako' Electrolytic Capacitors I've had these go s/c in 1970s Grundig tellies too.

3rd Jun 2015, 3:34 pm	#4
jjl Octode Join Date: Jan 2003 Location: Ware, Herts. UK. Posts: 1,082	Re: 'Frako' Electrolytic Capacitors I've seen Frako electrolytics in Revox and I think B&O kit. I've never encountered a faulty Frako though. John

3rd Jun 2015, 5:27 pm	#5
camallison Heptode Join Date: Feb 2013 Location: Yarm, North Yorkshire, UK. Posts: 535	Re: 'Frako' Electrolytic Capacitors They were probably genuine 1st quality ones then. Colin

4th Jun 2015, 7:47 am	#6
tri-comp Heptode Join Date: Oct 2008 Location: Aalborg, Denmark Posts: 903	Re: 'Frako' Electrolytic Capacitors When I see a 'Frako' cap. it triggers my 'Kill on Sight' gene. Must be a reason for that... /tri-comp

4th Jun 2015, 8:21 am	#7
'LIVEWIRE?' Rest in Peace Join Date: Mar 2006 Location: N.W. Oxfordshire(Chipping Norton) Posts: 7,306	Re: 'Frako' Electrolytic Capacitors They were almost always used in Blaupunkt Car radios & Stereos in the 70s & 80s, and no doubt in their domestic audio, etc., too. The only markings on the one I've replaced from the SM21 are on the top '2200/16' 'FRAKO' (in caps!) 'N I' , & '+'. This, and all theothers in the stereo are axial gold coloured types, all of which I will replace. Looks like they, like the 'horrible Hunts', waxies, & Plessey red & yellow Electrolytics, fall into the 'replace on sight' category, but then I guess none of the above were expected to last 40 or 50 years!!