RF_Test_Measure t #alignment #tool #smoke #file-notice


Timothy Fidler
 

I have added a Folder [see header of this post ](aka Directory ) and  under that a  PDF of the "standard " RF probe suggested for quick and dirty poking around in semiconductor based RF circuits with just a DVM as the measuring tool.  A couple of recent problems on 10W linear and 50W non linear amps on this BBS might have been solved in seconds  (bad solder joint crippling half of a symmetrical side of a class B amp in one case) if the builder had access to such a probe.  They can be build on a scrap of Vero board and glued with epoxy to an old pen barrel as indicated.
NB it has to be a PDF document as the  GroupsIO system treats any JPEG with text as a picture and I lost ALL of my typed text the first time.  A pox on them for designing the software to dump that text to the bit bin. !!!!

Wish list - 
Hans might like to put a copy of the schematic in each of his building manuals where such a probe is relevant. 

regards TE Fidler  Oct 2020


geoff M0ORE
 

Do you mean that you didn't bother to save??

On 03/10/2020 23:37, Timothy Fidler wrote:

 and I lost ALL of my typed text the first time.  A pox on them for designing the software to dump that text to the bit bin. !!!!

Wish list - 
Hans might like to put a copy of the schematic in each of his building manuals where such a probe is relevant. 

regards TE Fidler  Oct 2020


Timothy Fidler
 

FILE NOTICE  - SSB tcvr design by Weber but with Hans' VFO 

I have  also loaded the build instructions and  Schematic an P layout for the WEBER 75 m SSB radio into the files section under the 7 Mhz Linear amp banner.  this could be used with Hans '  DIGITAL vfo and a filter board  to produce a nice  3 watt (maybe) SSB tcvr. .  Fred at Far circuits still sells the PCB.  It is functionally the same as the 75m Survivor radio which was kitted by Hendrick's kits in California .. it may still be available in that way but only with a cruddy analogue VFO design from Steve Weber using a brass screw as the inductor core.. not less .

With a small amount of re-engineering which I could do it can be a 40 m TCVR as well.  between Hans,  the Toroid King and Far circuits you can get nearly all the parts you need.  I have an Enq out on Futurlec.com  (ALAN)  at the moment about the procurement status of DIP SA 612 mixer chips.  The Toroid king no longer has them in DIP and they are going the way of unobtainium ... .  SOIC and a carrier board which FUTURLEC sell (as do others )  is an option but more expensive and not beautiful.


best regards.  from the serial poster Pest ,  TEF 


Timothy Fidler
 

FILE Notice SSB Board  SSB tcvr design by Weber and PCB by FAR Circuits  but with Hans' VFO 

I did an update to the Weber75mGraphicOnly  file today.. after review of the PDF of the  Weber 75m Survival radio sold by Pacific Antennas (the PDF of build instructions ) there are some serious issues with the original design that was the basis for the FaR  circuits PCB. 

The Weber 75m Survival radio sold by Pacific Antennas is very expensive for what it is. You'd be better off with the MST3 mulitband from Ozqrp in NSW for the  money.

It probably can be made to work properly but cut and splice but it is not in the format  used in the working board as sold commercially from California.  In particular you need to get hold of the  FQN1NS50CT4A MOSFET  to do one of the RF receive revisions. These parts  are not currently listed on Ebay. So they have to come from a professional supplier.  That will be impossible for a one off purchase.

Fred of Far circuits as well as Dan IN Missouri still has access to the type 42IFT  10.7 Mhz IF cans used in this transceiver but perhaps not for much longer. They are New Old Stock parts.

regards  TEF