CR-620 FM stereo doesn't work anymore

[Eastham]

have seen those sort somewhere . cant remember where now though .
well done finding it so quickly . led lights dont go bad that often .

Me too, I think it was on RS I saw them, I can't recall though. Thanks I just traced the components that feed pin 4 back to the point I got voltage again, on the cathode of the LED, swapped it with a good one, voila! Took me by suprise aswell, though I guess being 40 years old, it may have been a little tired.

http://www.newark.com/kingbright/l-13id/led-2mm-red-8mcd-617nm/dp/87W9950

My hero! Looks like it will work.

 

[petehall347]

L-13ID

 

[Eastham]

L-13ID

Yep RS stocks them, gonna order a bunch. Thanks again Pete!

 

[Eastham]

Delivery guy never showed up today, guess it's going to be Monday. What the heck Parcelforce.

 

[avionic]

Delivery guy never showed up today, guess it's going to be Monday. What the heck Parcelforce.

Its a holiday.. St. Patricks Day..

 

[Eastham]

Its a holiday.. St. Patricks Day..

Good point, I completely forgot about that...

 

[petehall347]

check your order status . i once ordered some caps and turned out they were out of stock . phoned them out of hours .was before 9pm . they had them flown over from Germany overnight . i got them next day

 

[Eastham]

check your order status . i once ordered some caps and turned out they were out of stock . phoned them out of hours .was before 9pm . they had them flown over from Germany overnight . i got them next day

RS marked them as dispatched and the Parcelforce website said they package was prepared for delivery at 2AM on Saturday. Looks like they'll be here tomorrow. I always buy from RS for that reason, excellent customer service and free next day shipping on all order no matter what the final total is.

 

[Eastham]

Parts came in today, replaced all the LED's and balance has been restored to the universe. Thanks again Pete.

 

[petehall347]

no problem .

 

[avionic]

Look'n good..

 

[avionic]

Another source for the pin hole LED's
http://www.futurlec.com/LED/LED2PINRpr.shtml

 

[Eastham]

Another source for the pin hole LED's
http://www.futurlec.com/LED/LED2PINRpr.shtml

Thanks for the link.
One thing I have noticed about the LED's is that they're much brighter than the originals, not sure if that's down to the originals getting dim with age or the new ones just being brighter.
Another thing I've noticed is how good this receiver sounds, I don't know why I ever removed it from my system, I thought my Nad, SX-737 and Sherwood, but this. It's in a higher league, everything sounds so realistic and the detail in the vocals, drums, cymbals, bass, I can hear that the bass guitar is a guitar and not just some loud thoom and the sound stage is really spacious. It's by far the most detailed amp in my collection, and it's going to be back in my system for a while, maybe until I can get it's bigger brother the 1020 or a CA-1010, just gotta wait until I find one or the other for the right price.
DC offset still seems happy, 0mV left and -6mV right.

 

[avionic]

Probably just being brighter.

 

[petehall347]

there should be dropping resistors for the led.s . you could try higher values or first measure voltage drops across them to work out current draw .

 

[Eastham]

Probably just being brighter.

Probably, I know some early LED's where much dimmer than new LED's.

there should be dropping resistors for the led.s . you could try higher values or first measure voltage drops across them to work out current draw .

From what I can see in the schematic the only resistors are on the cathode sides of the LED's.

 

[petehall347]

thats likely them

 

[Eastham]

thats likely them

I'll have a mess round with some different value resistors. Think changing R214 could have an adverse effect on IC201?

 

[petehall347]

just been looking at that . not sure whats going on there .

 

[Eastham]

just been looking at that . not sure whats going on there .

Lol, right? I think Pin 6 of IC201 is supplied by the voltage going through the FM Stereo LED which is why I lost FM stereo when the original LED died.