View Single Post
Old 9th Jan 2006, 10:47 pm   #17
Join Date: Jan 2003
Location: Ashby-de-la-Zouch (it's not by the sea)
Posts: 825
Angry Re: KB FB10 'Toaster'

Well guys, the saga of the FB10 continues. I was busy installing capacitors to replace those that had been pinched by the phantom only to find some discrepancies between the beast itself and the Trader 969 Service Sheet. Let me explain ....

(1) C13 is down on the sheet as being 0.1pF, ok, we sorted that one – some kind soul told me that it should have read 0.1uF – much more sensible.
(2) C2 on the sheet is down as being 70pF. Fitted in my set was quite definitely a brown Hunts 001, 350V capacitor. Now if you read it literally as 0.001uF, this translated to 1000pF (which is clearly miles higher than 70pF). If one reads it backwards – ie 100 and assumes it to be 100pF then this is close I suppose, but here’s the but, removing it from circuit and measuring it with a Peak LCR reveals 1.8nF (ish) (which is close to 0.001uF). There was no sign of tampering around this component and the soldering was as black as all other untouched areas so what’s going on there I wonder? I have taken a couple of photos of the actual component that I removed.
(3) R2 on the sheet is quoted as being 220. No units are quoted, so we are probably led to believe that it is 220 ohm. Not so. The example in my set (and in the photos that were previously kindly provided) is quite clearly RED, RED, ORANGE which to my mind means 22000 ohm (22k).
(4) R13 is a mystery too.

So really the sheet isn’t that good is it. Can I believe anything it tells me – that’s the question? Does anyone know what the real values are please – particularly C2?

Many thanks one and all,

Attached Thumbnails
Click image for larger version

Name:	C2 KB FB10 001a.jpg
Views:	243
Size:	89.4 KB
ID:	2448   Click image for larger version

Name:	C2 KB FB10 002a.jpg
Views:	251
Size:	97.5 KB
ID:	2449  
af024 is online now