Hello,
For places you can not reach with a brush, as @Martaine2005 mentioned, you could use dust-off.
https://www.amazon.com/Dust-Off-DPSM2-Disposable-Duster-oz/dp/B009FFVOLK?th=1
Bertus
Hello,
Do you have details on the used inverter?
It sound like the output voltage is varying with the change of input voltage.
The regulation of the output voltage seems not to work well.
What is the input voltage range of the new inverter?
Bertus
Hello,
Perhaps a dedicated chip will do the trick:
https://ez.analog.com/adieducation/university-program/b/blogs/posts/hacking-an-led-solar-garden-light
More schematics here...
Hello,
Here you can find the schematics:
https://www.audioservicemanuals.com/p/peavey/peavey-xr/1335570-peavey-xr-696-xr800f-power-amp-schematics
More xr schematics can be found here:
https://www.audioservicemanuals.com/p/peavey/peavey-xr/
Bertus
Hello,
You could also draw your PCB's using Kicad.
It is free and available for windows, apple and linux:
https://www.kicad.org/
Minder posted a resource with a lot of tutorials for KiCad:
Kicad Tutoriol Source.
Bert
Hello,
How do you trigger the sensor?
Is the magnet strong and close enough?
Do you see the led change when the magnet is close to the sensor in my schematic?
Bertus
Hello,
An option would be a master-slave extention cord:
https://commons.wikimedia.org/wiki/File:Master-Slave-Steckdose.jpg
I am using one for my computer, to switch the boxes and monitor.
Bertus
Hello,
In the old days we used sharpy's for hand made PCB's :
http://www.stefanv.com/electronics/etching.htm
An other method is laser printer paper transfer:
https://www.giangrandi.org/electronics/pcb/pcb.shtml
Bertus
Hello,
It looks like the back of the casette player has some screws.
As @PETERDECO said, have a look inside.
Have a look at the pictures of this thread on stereo2go:
http://stereo2go.com/forums/threads/panasonic-national-rx-f-80-very-rare-mini-boomer-minty.1071/
Bertus
Hello,
Where did you get the VCO module?
What is the frequency range?
The modulation input is likely to shift the frequency of the module, like FM modulation.
Bertus
Hello,
Do you have a datasheet or other detailed info on the module?
I would take two resistors to make a voltage divider, to fix the modulation input on a fixed value, inside the range of the mentioned 0-4.5 Volts.
Bertus
Hello,
On HDMI it will be rather difficult as HDMI is digital.
VGA is analog and would be more easy to change.
Would this page help:
https://www.geocities.ws/podernixie/htpc/cables-en.html
Bertus