Re: The Jeffree Cell
Posted: Fri Mar 22, 2019 7:19 pm
Very nice bit of experimenting Harry!
Forum for discussion of television and imaging using mechanical, radio, and early electronic systems.
https://www.taswegian.com/NBTV/forum/
https://www.taswegian.com/NBTV/forum/viewtopic.php?f=12&t=2710
gary wrote:Very nice bit of experiment Harry!
Harry Dalek wrote:gary wrote:Very nice bit of experiment(ing) Harry!
I think i have to swap to a glass tube and hope the epoxy is less temperature sensitive ...PZT piezoelectric ceramic disk and even Quartz on the small scale shows heat is a problem after a while..... perhaps driving them much lower might fix it depends on whats needed .
I am not sure why but the PZT piezoelectric ceramic disk seems no better than a small quartz crystal with the valve Hartley oscillator seems to be 1.8mhz not 1.7 when i use that head scratching ~!
BTW Gary if you are interested in still making a Jeffree cell you are welcome to one of the WW2 crsytals with you want to go classic ! free of cause.
I am very interested Harry, all I have to do is get out from under this mountain of work I have to do. I am living vicariously through your posts at the moment but one day... So please keep going, I hope to join in with you one day.
Harry Dalek wrote:Just post me your address again
No PM here any more
Dave Moll wrote:Harry Dalek wrote:Just post me your address again
No PM here any more
You should be able to email by clicking on the "@" on the profile header.
Harry Dalek wrote:Thanks Dave it worked fine ...i have never tried since the PM trouble Andrews site had a while back.
Andrew Davie wrote:Harry Dalek wrote:Thanks Dave it worked fine ...i have never tried since the PM trouble Andrews site had a while back.
Mmh. Well, technically it's the NBTVA's site and I offered them full control/ownership but got no response.
I'm happy to hand over the reins; I don't want to appear to be taking over. It is a constant disappointment to me that the forum and newsletter don't co-exist rather than being independent entities. Anyway, that's my take on the situation. I don't consider it "mine".
Harry Dalek wrote:Yes its very strange Andrew ,you would think they would want it but as they say you can lead a horse to water but you can't make it drink.
I said it was yours as it was your idea to start it and a good idea it was too least i think it was its a story you have not told us of why ! I didn't know your thinking on it's belonging to or plans for the forum just hope it go's on on in the years to come .
Andrew Davie wrote:
It started because I wanted to build a televisor and I hoped that I could get people online to help me out. Since there wasn't a forum for that which seemed relevant, I thought I'd just start documenting the things I found/knew about NBTV and it went from there. A few very knowledgable people signed up and helped me out in my stumbling efforts to learn electronics and build my first televisor - which was shockingly bad, but worked
My concern is that the important information contained in the forum is not lost, especially if I disappear. I have made backups available, and shared passwords (I think), but it would be really nice to have some more formal management of data preservation in place.