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Growing up in Germany we had shopclass as well as technical drawing , later when I learned a trade we had to go to vocational school once a week and beside of all the electronics stuff we also had

Hi Adrian I think I must be a few years younger than you as I was born in !957 I started learning with the Philips electronic kits think it was called EE8 at the age of 10 but already dismantled a TV

I also grew up in the UK and was at secondary school (age 11-16) in the early 1960s and had the same experience as Paul, because I went to a village college we also had 2 hours a week of what was

Years ago I used ammonium persulphate to etch boards. I had a hard time convincing local chemical distributor I needed it. Appears it is also rocket fuel oxidizer. I used it in a bubble etch tank with

Hi Dave regarding good quality tools and how to use them In the UK when I was at school we had a minimum of 1 and a half hours per week of Metalwork , Woodwork , Technical drawing (total 5 Hours

Laminating the outlines would have the problem of placing them exactly so.? You're dealing with (at least as small) as 4 mm space between tracks and 4 mm tracks.? What many designers do for a 2

Good to know!? Thanks, Ross.Jim FordSent from my T-Mobile 4G LTE Device

Recycle my butt ?lol , when the etchant was Saturated it was dumped down the toilet

Was it possible to recycle the copper removed by these etchants? Was it possible in mass manufacture of circuit boards to laminate copper outlines of the crcuit paths, when there was substantial empty

Well it's good to be known for something, at least. :-) :-) I see your point. I think (and my thoughts on this are evolving with the help of this conversation) that the biggest problem I have is the

No activator, just plain chemical but i used a fishtank heater to warm it up

That's right. If you get too much volume increase of your solution by using it, some can be neutralized and it precipitates copper oxide out. The remaining water is low copper and neutral, so it can

Hi Lothar! Two questions: When you used Ammonium Persulphate, did you have to add an activator (few drops of something) to make it etch faster?? remember Kepro selling a small bottle with their "kit"

And store it outside if at all possible, and not on concrete.? It outgasses and will rust iron or steel. Harvey

Yes, and no. With an insulating resist, it will etch the copper away as long as there is active etchant in the tank. With a solder resist, the under cut is prevented by the action of the tin/lead.

Thanks everyone for the replies and for all the favourable comments about the 3458A. I forgot to mention that I have checked the power supply voltages and they are all OK. If I can’t make any

+1 for CuCl etching. Do use a wel ventilated area! Wilko

The best PCB films I ever managed to get were done by a friend who was into the offset printing business. They had film imagers at the time which could convert a CAD file into 4800dpi polyesterbase

Agree with the FR-4 Comments. The Dielectric Constant (ER and ER') changes based on manufacturer and other properties. As is always said, a Dielectric Constant, isn't. FR-4 changes based on Frequency.

I'm including this notification here, since this group also has many users of HPBASIC. I just added the 1999 Version of the TAMS HPBASIC Documentation CD contents to the files section in the VintHPcom