My CR-620 tuner is deaf, any suggestions?

Mad_Sunday

New Member
Hi, I only got this a couple of days ago and was so pleased with the look and sound of it, I posted how happy I was with the purchase. Today however I connected the tuner to an antenna (a known good one in a good location that worked fine with my old tuner) and it's deaf! I can only get a couple of FM stations and zero AM ones (on the ferrite rod). I suspect the front end is blown or there is some switching issue to the antenna connections? If I disconnect the antenna the signal drops out BUT if I move it close to the connectors the signal comes back (weak as before) as though some kind of capacitive link is being made. I'm not scared to get the soldering iron out (if the seller is willing to reduce the price) I've done plenty of component level repairs in the past.
So, what is the issue and how do I go about fixing it?

Pete

p.s. I'm listening to the amp now, it sounds wonderful, I'd really like to keep it. :music:
 
What type of antenna are you using? My 620 hates anything but dipoles for some reason.
 
The AM and FM are pretty much separate circuits, so it's interesting that both are bad. Check supply voltages on the boards first. Where are you?
 
I've got it hooked up to a folded dipole, and like I said, I'm in a good location on top of a hill (I picked the house for my Ham radio hobby) and even without an antenna I usually get plenty of signals. I'm in Staffordshire, UK so a good way fron New York :)

On AM all I get is a loud 50hz mains hum, even with the ferrite at 90 degrees to the unit.

Pete
 
Is not the polarization in the UK vertical as opposed to the horizontal polarization here in the U.S. I can scam the adjustment procedure into a PDF and using a strong station in place of a signal generator you might try an alignment.
 
As promised CR-620 alignment. Oh BTW there is a screwdriver adjustment in the end of the ferric stick antenna.
 

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Thanks guys, here's a quick update. The seller agreed to a partial refund of £55, so I got it for £45! yay!. I've ordered a set of bulbs from a seller in the States so when they arrive I'll have a mooch around inside and see if there's anything obvious. FM here in the UK is transmitted in both vertical and horizontal and "mixed" polarization, so that can be a bit of a lottery when choosing an antenna. However, like I said previously my Marantz receiver pulled in loads of stations with the same antenna so that can be rulled out. I'm just hoping no one's been "twiddling" in there. The fact that both FM and AM are bad is making me wonder if they aren't being selected properly by the switches.

Thanks, Pete
 
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