From: Paul Burridge
Subject: Re: Amplifying stage with *negative* Voltage gain??
References: <firstname.lastname@example.org> <3DF263CE.3868@Spam.Bots> <email@example.com> <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org> <3DF8BEAE.6391@Spam.Bots>
X-Newsreader: Forte Agent 1.8/32.548
Date: Thu, 12 Dec 2002 13:51:11 +0000
NNTP-Posting-Date: Thu, 12 Dec 2002 15:19:31 GMT
Organization: Virgin Net Usenet Service
On Thu, 12 Dec 2002 08:51:58 -0800, Mike Monett opined
>This was one of my original questions - what are you using for an
>oscillator, and why do you need an emitter follower?
I built the oscillator using a 40m Xtal from a published circuit. My
recollection is that you mustn't use the output straight from the osc
itself or risk stability problems. Hence the idea of using a
e/follower buffer stage. I then intend to make up a couple of voltage
amplifying stages followed by a low power PA.
>What kind of oscillator are you using? Can you post the schematic or give
>us a url?
I'm working on it right now.
>What's Stripboard? If it's what I think it is, you'd be much better off
>using copperclad as a ground plane, especially at these frequencies.
It's AKA "Veroboard" (tm) if that's more to your liking. I just didn't
want to advertise. :-)
So far as a ground plane is concerned, I'm surprised such construction
would be necessary at low HF such as 40m. UHF and beyond, then for
>There are many different styles ranging from Ugly to Manhattan. For
>quickies, I use an ordinary hot glue gun to mount components. If you scrb
>the copperclad with steel wool before starting, and keep your fingers off
>it, the hot glue sticks fairly well. When it's time to make another
>circuit, the parts can be removed without damage.
>I saw in other posts you are interested in working at higher frequencies,
>such as 40MHz. If so, you need to work with a ground plane for your
Hmmmm. I probably would, but don't believe stray
inductance/capacitance is likely to be a problem at anything below
50Mhz, if that's what your concern is. Still, I've been away from the
hobby for some 20 years so stand to be corrected!
"What is now proved was once only imagin'd"
- William Blake, 1793