Re: level and wave shape after balans mixer?
Chris van den Berg
Thanks for the additional information.
the correct schmatics are now at www.phonestack.com/farhan.I checked again http://www.phonestack.com/farhan/bitx.html and found
out that point 5 and 6 are stil wrong (not in accordance with the
data sheet, as noticed and posted by someone else).
I connected it correctly but an other person that follows the
schematic can have serious problems.
(if you make adjustments to your site, may be you can also add a
link to this yahoo group?).
The point is that I expected more output after the mixer. I am
always suspicious with that kind of coils (did I take the right one,
did I make the correct connections, is it really working the way it
should be) so I like to check something.
if you have already made the crystal filter, it is best that youmeasure
and check the signal at the output Q12 (without the RF mixerconnected).
I will work on it today and add directly the next stages to
terminate the filter as good as possible. I hope the output will
then be incresed some more otherwise I do not end up with enough
power at the end (or am I pessimistic ;-) ).
have you tested the receiver yet? it is usually the recevier thatcomes
alive first.The receiver works, while connecting a wire to Q3 I hear a lot more
then with the wire connected to the mixer.
i am convinced that we need to add detailed test measurements forthe
transceiver on the site. i have most of them in my log book. iwill post
them soon.In general, voltages can be checked easily to find out roughly that
the connections are correct and the correct values resistors are
mounted. Some general clues about what can be expected while
connecting a wire to a point or what voltage can be measured with
simple test gear would make it more complete indeed. May be current
with and without oscilator on (for every stage) will avoid the need
for more test equipment?
Adding too many measurement possibilities may be prevents a lot of
people building the design because they think it is all needed.
Doing the way you do now makes it important for everyone to
understand the circuit resulting in a higher level of radio
Other builders comments?