Re: building filters
With the software and connecting the output of the AF amp to PC, i wonder where do we set the BFO to find out the shape of our filter, assuming that we do not know the center frequency yet, or
By
Wijaya, J. <iyung_w@...>
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#903
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Re: building filters
Hi Chris,
Thanks for your answer. As you can see in my reply to Allison I will
follow your advices.
With you I hope that more pictures of the filtershape will be
dropped it in this group. The
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Ruud Jongeling <pe2bs@...>
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#902
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Re: IRF510 on higher voltage?
Chris
My BITX40 uses 24 volts on the IRF510 for a power output of 11 watts. It
required the addition of separate sheilding, 2 ferrite beads on the gate
lead, and a paracitic suppressor (2 ohm 2 watt
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Arv Evans <arvevans@...>
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#901
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Re: Questions about the amplifierstages in the BITX20.
Hi Allison,
Thank you for answering my questions. I understand that changing the
amplifier stage is not a good idea: variabels are depending on each
other and calculate the impedence is not easy.
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Ruud Jongeling <pe2bs@...>
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#900
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IRF510 on higher voltage?
Hi all,
did anyone tried to put higher voltage on the IRF stage?
If so, I am interrested about the results like:
- stability,
- increase of output power.
If the output power is not much higher and
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Chris van den Berg
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#899
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Re: building filters
Indeed measuring is knowing if the final result is in line with the
original expectations.
As mentioned before, it can be easily done with the sound card. At that
time, I asked for feedback
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Chris van den Berg
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#898
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Re: building filters
de 4N1ZM
I was looking in different designs of ssb trx and it looks like that
most important part is exactly filter. And that is place where
successful work of trx can easy fail. Crystals are
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Max
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#897
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Re: 6 m BITX ??
favourable candidates for a 6 m PA. The 2SC Japanes transistors are
more common and most likely much easier to use.
A line up of 2n4124, 2sc1970 and a pair of 2sc1971 will do
9-11W CW power at 12V
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ajparent1 <kb1gmx@...>
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#896
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Re: Questions about the amplifierstages in the BITX20.
The putput impedence is affected by both the load resistor and
feedback resistor value. Mismatch under 1:2(2:1) is resonable
for thos application.
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ajparent1 <kb1gmx@...>
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#895
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Re: building filters
Hi Ruud,
as I remember, you asked for a solution in the circuit, by using other
resistors.
I kept the circuit 'original' and added very small transformers,
pictures can be seen in the BITX17 Photos
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Chris van den Berg
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#894
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Re: 6 m BITX ??
Thanks for the good info dear Allison,
Yes, in the meantime I discovered MOSFET IRF's are not most favourable candidates for a 6 m PA. The 2SC Japanes transistors are more common and most likely
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Ron Brink <pa2rf@...>
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#893
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Re: Nobody is interested in PLL?
Allison, & others...
Since the time constant in an H&P (Huff and Puff) stabilizer is usually much
longer than that of a traditional PLL, a PIC-based H&P design might be quite
easy to implement. I
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Arv Evans <arvevans@...>
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#892
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Re: building filters
Within the base ladder filter topology there are subgoups of type.
They can designed as minimum loss, butterworth, linear phase or
Chebychev not unlike LC filters. Each has it's differences
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ajparent1 <kb1gmx@...>
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#891
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Re: Nobody is interested in PLL?
--- In BITX20@..., Jim Strohm <jstrohm@e...> wrote:
>
> On Jul 10, 2005, at 7:04 AM, Ashhar Farhan wrote:
>
> > while PLL chips are difficult to find, the 16F84 or the 16F628 are
> >
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ajparent1 <kb1gmx@...>
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#890
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Re: building filters
Hi Paul and Max,
Thanks for your info about the design of a ladderfilter. The
ladderfilter was subject in this group before. Building the BITX20 I
made a shape of the ladderfilter with the program
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Ruud Jongeling <pe2bs@...>
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#889
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R: Article about BITX20 on Italian magazine
Yes Paolo,
I'm a memeber of this list and just for this reason I discovered this good
RTX and decided to show to other italian Hams... hi!
Best 73
Alex I0SKK
-----Messaggio originale-----
Da:
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Alessandro Santucci - I0SKK <I0SKK@...>
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#888
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Re: building filters
de 4N1ZM
I added older easier for understanding version of ladder filter
desingn program in file section under 4N1ZM folder.
design.
build
ARRL
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Max
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#887
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Re: building filters
de 4N1ZM
There is two programs and alternative aproach to ladder filter design.
Since altavista translation can overcame language bariers it is
possible to check this link through systran
By
Max
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#886
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PCB Making Kits
Dear Friends
I wish to let you know that VUQRP will be making "PCB Making kit"
available to VU hams who are interested in homebrewing.
The price of the kits will be around Rs.325/- plus postage
By
Jyoti P. Chakravartty <csai@...>
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#885
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Re: Hey ;)
MODERATOR NOTE:
This message appears to be Spam - however Preethi Nair has been a member
since 27-Oct-04 and in that time has only made three postings, the first two
of which were radio related.
By
Hans Summers <Hans.Summers@...>
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#884
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