EMRFD Message Archive 2712

Message Date From Subject
2712 2009-02-20 06:46:03 Geoff Pike BD135 /BD139
I noticed this device mentioned recently in the posts, a very European
device. I have used this up to 70 MHz as a power amplifier.
The results at HF are useful.
The small gain block that i made with it had 50 mW in for 500 mW out
from a 13.8 V supply at 70 MHz.
A broad band HF amplifier was built also with reasonable results.
These devices have high Vceo ratings and hence may be amplitude
modulated. Never got around to checking IMD.
Geoff Pike
2722 2009-02-21 07:03:51 Michael Clarke Re: BD135 /BD139
Geoff Pike <gi0gdp@yahoo.co.uk> wrote:>>The results at HF are useful.

HI Geoff
You probably know that the BD135 was used as the PA in (for example)
the popular Howes CTX 80 Transmitter over 20 years ago. It gave a
sturdy 5 watts CW and had provision for AM input via key input. I
notice the CTX 80 for sale on GQRP list and on Ebay, still popular,
and fetching a price equal or more than that in the late 1980s!
Mick Mi5mtc
GQRP 9630
FISTS 7740