Wednesday, March 1, 2017

474.2 kHz report

another  good night  over 100 TA decodes

 WG2XXM   new one outside FN.
 decoded here much later then  a few hundred km west of me.
 No other goodies.  TX was repaired. fttb.  but no reverse decode
 Today I will have to remove at least the east Beverage.

New record signal strength    +1
2017-03-01 04:52  WD2XSH/17  0.475646  +1  0  FN42pb  5  PA0O  JO33hg  5630

 2017-03-01 05:26  WG2XXM  0.475710  -24  0  EM15lj  5  PA0O  JO33hg  7736  38 
 2017-03-01 00:56  WG2XKA  0.475721  -25  0  FN33lq  1  PA0O  JO33hg  5656  49 
 2017-02-28 22:50  WD2XSH/17  0.475647  -26  0  FN42pb  5  PA0O  JO33hg  5630  49 
 2017-03-01 00:28  WG2XPJ  0.475674  -28  0  FN34lp  1  PA0O  JO33hg  5587  50 
 2017-03-01 03:06  PA0O  0.475701  -27  0  JO33hg  0.2  SV8RV/1  KM07ks  2042  142 
 2017-03-01 03:06  PA0O  0.475700  -25  0  JO33hg  0.2  EA7HPM  IM67xj  2017  214 
 2017-03-01 04:58  PA0O  0.475740  -26  0  JO33hg  0.2  SM2BYC  KP25ax  1706  27 
 2017-03-01 03:42  PA0O  0.475740  -12  0  JO33hg  0.2  OH2EAT  KP20xw  1437  46 
 2017-03-01 03:06  PA0O  0.475700  -23  0  JO33hg  0.2  EB3FRN  JN01mc  1416  199 
 2017-03-01 03:42  PA0O  0.475742  -8  0  JO33hg  0.2  LA9IY  JP53  1162  11 
 2017-02-28 22:06  LA2XPA  0.475782  -11  0  JP33wi  0.2  PA0O  JO33hg  1124  184 
 2017-03-01 03:08  PA0O  0.475700  0  0  JO33hg  0.2  LA2XPA/2  JP33wi  1124  3

first decode
2017-02-28 22:50  WD2XSH/17  0.475647  -26  0  FN42pb  5  PA0O  JO33hg  5630
last decode
 2017-03-01 08:06  WD2XSH/17  0.475646  -26  -1  FN42pb  5  PA0O  JO33hg  5630

New project

A QRP-LABS  U3S  kit is under construction.
The  U3S "de luxe" is build for Willem
 PU7ZWT / PD0OHW  the goal is  to set up a WSPR  beacon in Brasil  WWLOC:  HI11ln
at 10 12  and 6m
The De Luxe kit contains all needed units  a 5W PA is an option  

The single BS170 at 5V   170mW 30m 150 12M 150mW 10m  100mW 6m.
At 12V  500mW but the single BS170 can not handle that in the plastic TO92.   

Most parts are complete

Very good and interesting manual of 46 pages
Besides that there are individual unit assembly documents.
This is not a one evening project.
The QLG1 GPS receiver board has its onboard  2.5x2.5 cm 1574 MHz antenna directly connected to the
YIC51612  GPS receive chip.  fix  6 -8 satelites under the roof on the workbench.
The small antenna works good I was not able to receive satelites with a 2nd QLG1 using pieces of wire.
But it takes long from cold start after a long power down to get a fix  20m and more indoor.
Once it has a fix the onboard Li- cell preserves data during short power outage 10 20 sec or so.
Then a FIX happens quick.
An optional a SMA for an external active GPS antenna with 3,3V injected instead of the integrated antenna is possible.

But the QLG1 with integrated antenna can  be connected external over distance to the D9 g.p. connector
Using a 4 wires data cable  10m or more must be no problem  to place it at the best spot.
This cable only needs to carry 5V gnd 1 pps and NMEA serial data 9600b.

Testing of the 5W PA  has to wait for arrival of the RD15HVF1 transistors.
Expected  more output at 12 10 and 6 then with the original IRF510.
The goal is 5W on those 3 high bands
The IRF510   measured about 400pF at G-S 0V the lowest G-S capacitance of all IRFxxx types
 f.i. the IRF540Z is about 2500pF    the highpower  IRFP4227  measured 7500pF
This one needs a special mosfet driver TC4422  that can handle 4nF load
At 474.2 kHz  I tested the IRFP4227 in the QTX, the  driver uses a transistor pushpull driver that can not handle the  4nF + load  no output the 10V  BlockVoltage drops to a few volts

Some bad luck 2 broken Si5351A ?   one by statics in an earlier ProgRock project
A defective 5V supply killed the 2nd  plus a Arduino nano.
The Si5351a P1 2 3  outputs are very ESD sensitive . Best is to ESD protect outputs right away with diodes. 

I have a cheap and nice breadboard power adapter  5V 3,3V  selectable 
But it supplies maximum 200mA depending on the Voltage drop.
The SMD stabilizer heaths up very quick  as the input normal will be 12V
But even at 9V  power is restricted.
A max 5V protector is very recommended ! Mine went up to 8V 
I was lucky that my DDS AD9850 board still works
Strange that the Si5351A  broke  it has its LM317 3V3 regulator.

The Si5351A is a cheap clock generator chip  I2C controlled up to at least 200MHz 
3 programmable outputs  list prize 1$ at the big electronic suppliers
Possible not usable in all applications the I2C data exchange seems to cause a short interruption in the output?
I will try to fix the 2 Si PCB's
Handling and shipping costs are high for  just a few pieces  18€ or more.
But our local Electronic shop OKAPHONE   since 1930!   
supplies it for 2,10€  in a few days very reasonable.
Most electronic shops here disappeared long time ago.
The webshops took over

                                       The breadboard power adapter type that can burn out be aware!