[time-nuts] Fwd: Re: Frequency Distribution Design Basic Module

timeok at timeok.it timeok at timeok.it
Sat Aug 22 09:45:16 EDT 2015

 Hi Attila,
> >
> > I just like to learn from other people :-)
> > Oh, and btw: actually, a list of what you tried and what didn't work,
> > especially why it didn't work, would be a lot more interesting than
> > the final design.

As for the amplifier the big job was finding the balance between the
polarization parameters, harmonic distortion and output power.
Many distribution amplifiers on the market have a Po max of + 13dBm and
this limit does not seem appropriate for this century.See table.

 The most important challenge left a bit open is on the power supply.
Starting from the end, linear regulator, the DC switching circuit I think,
 is great and does not require further investigations, while you can always
 improve the choice of AC-DC switching power supply. When I chose the
 Medical grade PSU is for high MTBF since it was built to work 24 hours a
 day. All the Power section is configured looking to a low thermal
 dissipation, especially in regards to the linear regulator. A great
 experience was on the passive filter after switching PSU. I could see that
connecting the negative pole to ground only after the balanced filter it is
 obtained excellent attenuation of switching output spike.
> > That sounds reasonable. 40EUR isn't much. But i am not sure whether you
> > can produce them for that price. Guestimating you have 15EUR cost in
> > parts,
> > that would mean something around 40-100 parts on the pcb. For that, the
> > setup costs should be somewhere in the 200-500EUR region, probably
> > around 300. Assuming another 10EUR for the work, that means you have
> > to produce at least in batches of 15 get below 40EUR/piece (using 200EUR
> > setup cost). So anything below 50 pieces batches does not sound
> sensible.
> >
Obviously the difference is the quantity.
Mount smd by hand is not easy especially if you want a good result. Mount
 them to machine has high initial costs and high average quantities required
to lower the total costs.
You must also consider the necessary cleaning products, PCB thread for
nylon screw, preparation of the coil etc..
Currently I still have 24 pieces I could sell, ready for use, 40 Euro
 The six-channel version will be ready in 12 months or more. You can pair
 two cards to have 12output channels with a single input channels or 2 x 6
 output channels if you want to have a double DA to distribute, for example,
 5 and 10 MHz.
 Thank you for your comments,
see: http://www.timeok.it/wp/ [1]

Message sent via Atmail Open - http://atmail.org/
-------------- next part --------------
A non-text attachment was scrubbed...
Name: comparative table.ods
Type: application/octet-stream
Size: 19226 bytes
Desc: not available
URL: <http://www.febo.com/pipermail/time-nuts/attachments/20150822/d7d9e9f3/attachment.obj>

More information about the time-nuts mailing list