Is one of these a griplet?

[Bayou Self]

Referring to the round holes on this Philips PCB, both sides shown.

 

[Bayou Self]

If anyone can point me to a griplet, that would be great! I read something about some of them being diamond-shaped...are they all like that?

 

[Galu]

As you are probably aware, griplets are used to connect stacked circuit boards together via wires soldered between the griplets.

Some griplets are visible in the attached image. They basically look just like blobs of solder within a metal ring.

 

[Galu]

Apparently, griplets were shown as diamond symbols on the circuit diagram.

Attached is a better image showing what they physically look like (wire sticking through an unsoldered one)..

 

[awkwardbydesign]

I'm so glad I know that now. I shall try to work it into a conversation.

 

[Bayou Self]

Thanks, Galu!

 

[Galu]

I'm so glad I know that now. I shall try to work it into a conversation.

Get a griplet!

 

[Bayou Self]

Could someone please tell me what these are? My board has 12 of them.
Also, there are 3 components on the back side...one is labeled TDA8808T and has the Philips logo.

 

[Mark Tillotson]

Apparently, griplets were shown as diamond symbols on the circuit diagram.

Attached is a better image showing what they physically look like (wire sticking through an unsoldered one)..

I just see a pad on the groundplane using thermal relief.

 

[poynton]

Could someone please tell me what these are? My board has 12 of them.
Also, there are 3 components on the back side...one is labeled TDA8808T and has the Philips logo.

What player are you working on ??

The picture seems to show 2 griplets .


Andy

 

[Bayou Self]

@poynton
The unit is a Philips CD-60.

@Mark
You mean those three blobs in post #8 are like heat sinks?

 

[Galu]

The Marantz CD-50 is basically the same machine. The circles (your 'blobs') and their associated wire links are shown on the circuit board on page 17 of the service manual, which should reveal their purpose.

http://www.hifisounds.co.uk/manuals/Marantz_CD50.pdf

 

[Bayou Self]

I found the circles on the page of the SM, saw that they are listed under mechanical parts, saw on the schematic that some traces terminate under the circle, but cannot find that symbol's description. Googling the part number did not reveal anything. I'm ready for my next clue!

 

[Galu]

I can only supply you with more information on griplets!

Griplets (also known as 'vias' or 'through board rivets') are used to connect the ground planes on stacked pc boards together.

A multimeter should confirm continuity between the griplets themselves and to the ground plane as well as the trace side where the griplets connect.

 

[JeffYoung]

The whole thing is curious. There are jumpers all over the board, yet it's a 2-layer board. So why the jumpers, instead of just traces? Maybe it has no plating in the holes or something?

Anyway, the blobs connect the jumpers to the ground plane. Again, why not use a via directly to the ground plane?

 

[Bayou Self]

I appreciate the help, but I'm getting lost.
1. Is the ground plane on both sides of the board?
2. If the back side of my board has 3 components, one of which is a SAA7310GP, does it qualify as a double-sided or stacked board?
3. Do need to drill a hole through the blobs and solder the ends of a wire to each side of the board?
Thanks!

 

[poynton]

Why are you so concerned with griplets?

 

[JeffYoung]

No, the ground plane is only on one side (the one with the blobs).
Double-sided just means it has copper on two sides; the location of components is another matter.
There are traces on the other side of the board under the blobs. Drill through them and you'll short those traces out.

 

[Galu]

Bayou, care to tell us what your problem is in the first place?

 

[Bayou Self]

@Jeff Thanks.

@poynton I know you had recommended the "griplet mod" in previous threads, but looking back, it seems all of those threads concerned the CD 104, so it may be I can quit worring about them!

@Galu Originally, the 650Hz wobble frequency was so loud I could hear it over the music (I sit close to the machine). I took it apart to replace some caps, and now it won't recognize a disc. I'm not throwing in the towel yet, however.