About BITX PCB
Hello from EB1CPC / EC1ACV , in Spain.
I try to build the BITX20. I have the PCB but I have many doubts about the location of
many components in the PCB.
Can anybody help me?. Anybody send me the
By
Roberto Suárez <RADIO_EB1CPC@...>
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#206
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Cap Meter and Freq Counter projects
HI Folks, I've just found this url in a newsgroup that may be of
interest to someone out there :-)
http://www.qsl.net/k1jhj
Using AVR's in both projects, with free development software, free
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Mike W <mike@...>
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#205
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IF filter passband measured
Hello,
I have just uploaded a file with the results of my measurements of
the IF filters passband.
The set-up was a DDS-VFO as a signal source and a HF millivoltmeter
as a detector.
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Heinz Schnait <oe5eep@...>
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#204
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Re. problem with crystal oscillators
MILAREPA@.............
It would appear from your chart that the higher frequency crystals may
not be oscillating, or that your frequency counter may not be capable of
counting above 10 MHz.
Lets
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Arv Evans <arvevans@...>
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#203
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Re: CRYSTAL MEASUREMENTS
Dear forum,
==About Crystal Measurements==
At the time I mail to BITX about this subject,
'actually' I was using a 3.579545 MHz crystal, that available
at my junkbox and drifting is in this
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MILAREPA <MILAREPA@...>
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#202
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Archive message settings
Following a suggestion from Dave M1DGS I have enabled the group message
archives for reading by non-members. This means that visitors to the group
are now able to view all of our messages in the
By
Hans Summers <Hans.Summers@...>
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#201
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Re: Binocular Cores
Mike
Some time ago (actually, many years ago) I remember reading somewhere
that you can make up your own "binocular cores" by stacking two rows
of conventional toroid cores. That's about all I
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Arvid Evans <arvevans@...>
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#199
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Spam message
Hi
Sadly it appears that a spammer has joined our group and sent a spam email
which I received here at 1809 UTC.
I have deleted the offending message from the messages archive, but those of
you
By
Hans Summers <Hans.Summers@...>
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#198
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Measuring Crystal & IF Filter Frequencies
Hi
Hans' comments (see below) are very appropriate to the measurement of
Crystal frequencies. I too found that if you solder the crystals in
place, it may be necessary to wait several minutes for
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Arv Evans <arvevans@...>
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#197
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Re: CRYSTAL MEASUREMENTS
Your circuit and method look Ok to me... how bad is the drift, and what
happens if you wait longer than 5 minutes? The drift could also be in your
frequency counter (or PC if you are using that as a
By
Hans Summers <Hans.Summers@...>
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#196
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Re: BITX20 & BITX40
Hi Arv,
Thanks a lot for the very detailed reply to my query and for offering to advise me on any problems I might face with building the trx.
Knowing that I can bank on the group's knowledge and
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Bharat Balsavar <vu2bdx@...>
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#195
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Re: Inexpensive plastic screwdriver
Paolo
In the US, plastic knitting needles are available for an attractive
price. These range from 1/8 inch to 1/2 inch diameter. The smaller
ones are easily ground to a screwdriver point using
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Arv Evans <arvevans@...>
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#194
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Re: BITX20 & BITX40
Bharat
The discrete component AF Amplifier file is in the FILES and PHOTOS
sections of the BITX20 forum on Yahoo.com You should be able to view
and copy them from there. If you have problems please
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Arv Evans <arvevans@...>
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#193
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Binocular Cores
I have found a 'source' of minature binocular balun cores in old UHF
TV tuners and computer UHF modulators. there are usually, it
appears, one or two per tuner. Not tried them yet though.
atb Mike
By
Mike W <mike@...>
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#192
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CRYSTAL MEASUREMENTS
Dear forum,
I try to measure my 12 MHz IF-crystals with method here,
for purpose selection within 30 to 50 KHz ( is this value right ? ).
But the problem is:
Frequency reading is still moving /
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MILAREPA <MILAREPA@...>
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#191
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Re: Inexpensive plastic screwdriver
Hi Paolo,
I cut/filed a piece of PCB to the right size and
sanded of the copper. The slight advantage over a
toothbrush is that the material is less soft, so it
can handle screws that are tight or
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Hubert Smits <hubert.smits@...>
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#190
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Re: Inexpensive plastic screwdriver
Mike W wrote:
WOW! Got to ask my mother if she has some spare plastic ones!
For those non-native English speakers that might wonder what a "knitting needle" is, see the description here
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Paolo Cravero as2594 <pcravero@...>
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#189
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Re: Inexpensive plastic screwdriver
Whats wrong with the old plastic knitting needle ?. When playing
with HV circuits they are a lot longer and therefore safer.
Another useful tool is a tuning wand, brass ferrule on one end of a
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Mike W <mike@...>
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#188
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Relay question Help!
Hi!
I recall reading about the two relay placement being helpful in avoiding RF pickup.
I would be obliged if the someone will give me the new configration.
73
Rahul VU3WJM
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Rahul Srivastava <vu3wjm@...>
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#187
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Re: Inexpensive plastic screwdriver
Hi!
I fashion them out of glass epoxy PCB material. Much scrapped double sided PC boards are available.. cut a strip from area without copper traces ie normally the edges .
File and shape the strip
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Rahul Srivastava <vu3wjm@...>
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#186
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