xpyttl wrote:

Hi

Also take a peek at some of the TI stuff. They have synthesizers and
"transmitter" chips that are very reasonably priced. Although they are
intended for very high frequencies, Steve Weber has made them work down into
more reasonable frequencies, and prescalers are only a couple of bucks.

Do you have any reference to Weber's project? I would love to have a
look at that circuit!

BTW, do you mean SteveN Weber, KD1JV?

Thanks,
Paolo IK1ZYW

I do mean KD1JV. However, I don't think Steve ever wrote anything up. If I
recall, he used the TRF4900 which is a "transmitter" - basically a DDS with
an amplifier. The 4400 looked a little more interesting to me, same thing,
lower frequency. I've been meaning to do something similar for a while now.
I had assumed that you needed to operate these parts somewhere near their
spec frequency, 900 MHz for the 4900, 450 for the 4400. Steve went right
down to 6 meters for his first whack and had no problems.

What is interesting about these is that they are reasonably priced, and the
frequency steps are small enough that you are in the neighborhood of a Hz or
two after dividing them down to HF, reasonable for a CW rig. They are also
easily obtained.

TI also has a series of synthesizer chips, the 2050 and 2052 that seems to
be a bit more flexible, but maybe more complicated. All these parts are
under five bucks quantity one.

I have to admit, after getting over my shyness over asking AD for samples,
the AD parts look a lot more appealing. But I have a few of these TI chips,
and I finally got a prototyping board that will work with them, now if I can
just get the time to play with them...

...

"PaoloC" wrote in message
...
xpyttl wrote:

Do you have any reference to Weber's project? I would love to have a
look at that circuit!

BTW, do you mean SteveN Weber, KD1JV?

I do mean KD1JV. However, I don't think Steve ever wrote anything up. If
I
recall, he used the TRF4900 which is a "transmitter" - basically a DDS
with
an amplifier.
Steve went right
down to 6 meters for his first whack and had no problems.

If they can be taken down to HF also, it would be very easy to make a CW tx
for 17 - 10 meters with such DDS-PLL chips. Right now that is not so
interesting, but by the time we approach the next solar peak (2008+?), there
may be many more such chips available also.



--
Sverre Holm, LA3ZA
---------------------------------
www.qsl.net/la3za

Sverre Holm wrote:


down to 6 meters for his first whack and had no problems.


If they can be taken down to HF also, it would be very easy to make a CW tx
for 17 - 10 meters with such DDS-PLL chips. Right now that is not so
interesting, but by the time we approach the next solar peak (2008+?), there
may be many more such chips available also.

Yep, and in smaller packages too! :-) Those mentioned by xpyttl are in
TSSOP packages if I recall correctly: way too small to hand-solder!

Sometimes I am "frustrated" by the huge amount of useful ICs for HAM
homebrewing shipped in ultra-space-saving packages. :-(

Ciao,
Paolo IK1ZYW

"PaoloC" wrote in message
...
Sverre Holm wrote:


down to 6 meters for his first whack and had no problems.


If they can be taken down to HF also, it would be very easy to make a CW
tx
for 17 - 10 meters with such DDS-PLL chips. Right now that is not so
interesting, but by the time we approach the next solar peak (2008+?),
there
may be many more such chips available also.

Yep, and in smaller packages too! :-) Those mentioned by xpyttl are in
TSSOP packages if I recall correctly: way too small to hand-solder!

Sometimes I am "frustrated" by the huge amount of useful ICs for HAM
homebrewing shipped in ultra-space-saving packages. :-(

TSSOP is easy to solder using the 'drag soldering' technique. I use a
special Metcal system with a hoof tip, but it can be done with ordinary
soldering equipment. Plenty of liquid flux is the secret to success.

Leon
--
Leon Heller, G1HSM
http://www.geocities.com/leon_heller

"PaoloC" wrote in message
...
Sverre Holm wrote:


down to 6 meters for his first whack and had no problems.


If they can be taken down to HF also, it would be very easy to make a CW
tx
for 17 - 10 meters with such DDS-PLL chips. Right now that is not so
interesting, but by the time we approach the next solar peak (2008+?),
there
may be many more such chips available also.

Yep, and in smaller packages too! :-) Those mentioned by xpyttl are in
TSSOP packages if I recall correctly: way too small to hand-solder!

Sometimes I am "frustrated" by the huge amount of useful ICs for HAM
homebrewing shipped in ultra-space-saving packages. :-(

TSSOP is easy to solder using the 'drag soldering' technique. I use a
special Metcal system with a hoof tip, but it can be done with ordinary
soldering equipment. Plenty of liquid flux is the secret to success.

Leon
--
Leon Heller, G1HSM
http://www.geocities.com/leon_heller

Sverre Holm wrote:


down to 6 meters for his first whack and had no problems.


If they can be taken down to HF also, it would be very easy to make a CW tx
for 17 - 10 meters with such DDS-PLL chips. Right now that is not so
interesting, but by the time we approach the next solar peak (2008+?), there
may be many more such chips available also.

Yep, and in smaller packages too! :-) Those mentioned by xpyttl are in
TSSOP packages if I recall correctly: way too small to hand-solder!

Sometimes I am "frustrated" by the huge amount of useful ICs for HAM
homebrewing shipped in ultra-space-saving packages. :-(

Ciao,
Paolo IK1ZYW

I do mean KD1JV. However, I don't think Steve ever wrote anything up.

Here's his account using the TRF4400:

http://www.kkn.net/archives/html/QRP.../msg01621.html


--
Sverre Holm, LA3ZA
---------------------------------
www.qsl.net/la3za

I do mean KD1JV. However, I don't think Steve ever wrote anything up. If
I
recall, he used the TRF4900 which is a "transmitter" - basically a DDS
with
an amplifier.
Steve went right
down to 6 meters for his first whack and had no problems.

If they can be taken down to HF also, it would be very easy to make a CW tx
for 17 - 10 meters with such DDS-PLL chips. Right now that is not so
interesting, but by the time we approach the next solar peak (2008+?), there
may be many more such chips available also.



--
Sverre Holm, LA3ZA
---------------------------------
www.qsl.net/la3za

I do mean KD1JV. However, I don't think Steve ever wrote anything up.

Here's his account using the TRF4400:

http://www.kkn.net/archives/html/QRP.../msg01621.html


--
Sverre Holm, LA3ZA
---------------------------------
www.qsl.net/la3za