Well I've now got IC7 in the right way round, but it's not quite the unqualified success that Paul seems to have had.

The AM reception is now good and clear but the signal strength on FM is now not registering more than one or two bars and I can't hear anything. This is still set up on the bench with a spare (but new) car aerial so maybe it will be OK in the car. However I think, to be on the safe side, I'll get a new CA3140 from Maplins tomorrow (they're only 60p) just in case I've fried part of the chip. Oh well I should have paid more attention in the first place !

Is it possible that I have damaged any other parts by having IC7 in the wrong way round?

Geoff

OK if anyone is still interested after all this, here's the latest !

Got a new CA3140 from Maplins (2 actually just in case !) and replaced the one that I had put in the wrong way round and desoldered/soldered.

Connected it all up and ...................still no FM

It seemed that connecting the aerial made no difference, which made me suspicious, and on inspection, the RF lead, having been removed so many times from the case had broken where it joins the PCB.

I resoldered the RF lead and (at last) I had full FM reception including RDS

I've just re-installed it in the car and have still got excellent FM although the AM is a bit flaky. It was fine on the bench so maybe the VW amplified aerial is causing the problem. I'd be interested to know if any other VW owners have the same problem with AM.

Anyway FM is now 100% and, apart from the odd football match on Radio 5, I can't see me needing AM anyway, so I'm 99% happy

Thanks for the help on this, and thanks to Patrick for a great product - my problems in no way reflect badly on your instructions - I'm just an idiot !

Geoff

Hi Geoff,
I own aLuipo, but we do have the same antenna. I don't have an empeg, but I'm not too happy about that antenna VW puts on our cars. While it's okay if you have an original VW HeadUnit, it just doesn't work well even with Blaupunkts, at least on my two Lupo's I've owned; and before someone asks: I used the adapter...so what I'm trying to say (in my not-so-good english..) is that I?m going to change the antenna for a non-VW one, one that has a normal lead coming out where you have to connect 12v + . Maybe this could "solve" your AM problem? But it's probably not an easy job to change the antenna in a Golf; as it's not quite easy on a Lupo.

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I resoldered the RF lead and (at last) I had full FM reception including RDS

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Yay, glad you finally got your tuner working!

Yeah, I'd suspect the antenna too. My VW Golfs reception (AM or FM) with it's 'amplified' antenna is not as good as the bog standard non-amplifed antenna in my wife's '93 Mazda.

>I've just realised my mistake- I've put the MAX4544 in the wrong way round.

Now that I have a couple of kits here, I can see how easy it is to make that specific mistake: The writing on the chip is "upside down" compared to the silk-screened writing on the circuit board.. so naturally we want to flip it around..

-ml

I PMed Patrick about this, but maybe i'll get an answer here faster.

Can someone tell me if the left hand leads of R10 and R30 and the right hand leads of R30 and R29 have traces connecting them on the board? I think i might have scraped of the traces thinking it was a joined solder joint....

I don't have my tuner kit with me at the moment but I may be able to help. Patrick posted a link to the screen grab of the PCB layout which is here and from squinting at the correct position it looks like you've chopped out two traces by accident...

If you mean that R10 and R30 are connected together on the left hand side then yes.
And R30 and R29 are connected on their right hand side.

- Trevor

DOH! No problem... a little solder to bridge the gap and i'll be fine. Heh...

mental note: don't solder tiny components at 2:30am

since we have been speaking of chips backwards and so forth, quick question...having trouble so far having success (although only had about 2 minutes to attempt installing in car) with the tuner kit. I do remember one of my chips, can't remember if it was max or ca, did not have a notch out of either end, am I to assume that the recessed dot on the corner also specifies direction? I installed the chip assuming the recessed dot stood for the missing notch.
thanks

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am I to assume that the recessed dot on the corner also specifies direction?

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Manufacturers put the "dot" next to pin 1, so yes. Some even have both a notch and a dot.

Stu