AGH! Why do things keep breaking on me?!

[redk9258]

Does anyone have any advice or tips on how I can safely adjust the bias?

Make sure you use insulated mini grabbers. Don't try to hold probes. You WILL slip and short it out!

 

[PE9ZZ]

See that depressed screw hole? I noticed that there was a metal plate on the PCB for where that screw is supposed to go. This made me realize that this service panel is acting as a ground for one of the PCB components. As soon as I screwed the panel back in, the receiver fired right up without any issue! Man, oh man. I was getting really worried...

Did not see that coming... Sloppy design (see attached crop of PCB)

 

[Saffire]

Did not see that coming... Sloppy design (see attached crop of PCB)

Absolutely, so it's some kind of ground for two pins of the filter caps. That's really frustrating, because I like to test things and make sure that they work before putting it all back together. And making the service panel a grounding point is a great way to cause stress!

 

[PE9ZZ]

Well, it is the grounding point. Having it float screws up everything. Bad engineering and a real gotcha (or instinker as the Dutch phrase goes, and yes, it stinks).

 

[GChief]

I'm going to pick up a digital multimeter and see what I can do.

So you jumped in without anyway to do even basic checks? Between this and using the wrong flux you need to put down the tools and back away.

 

[Saffire]

So you jumped in without anyway to do even basic checks? Between this and using the wrong flux you need to put down the tools and back away.

This probably sounds stupid, but I didn't think a DMM was important. Now that I have the receiver fixed, I didn't really need a DMM in the first place for this job.

 

[gadget73]

isn't this a grounding point?

I'm amazed they used a removable panel as a ground. Definitely not what I'd have pegged as the problem either.

a working reliable meter is an extremely useful tool. Everyone should have one and know how to use it IMO.

 

[Saffire]

I'm amazed they used a removable panel as a ground. Definitely not what I'd have pegged as the problem either.

a working reliable meter is an extremely useful tool. Everyone should have one and know how to use it IMO.

Absolutely! I should have bought one a long time ago, I currently have one coming via Amazon.