Thursday, October 6, 2011

Early Sputnik QSO Party Results

We're now two days into the Sputnik QSO Party and everything is coming up roses. Today for example, the first signal that I heard on 15m was ON6WJ's tidy Sputnik "clone"  beeping across a distance of 5550km with an output power of 700mW. Here's a photo of Josef's excellent handiwork.

  

Please visit ON6WJ's "Sputnik Made in Belgium" page by clicking here.

On the evening of the first day of operation I had this note from Colin, G3VTT.

"I used the Sputnik TX at powers of 400mW and 700mW with 80 volts and 110 volts respectively although keying was better at the lower voltage and oscillator start up more reliable. My circuit used link coupling tuned with a 60pf trimmer to the antenna and HT keying of the PA.

I worked UA1ASB, RK1NA, SM4EVC who gave a report and then sank into the noise, RA3AL, G3TYB up the road and W9RGB. This last QSO was a real one with 'intelligence' passed as Vic told me he had last heard the Sputnik signal whilst at college in '57.

I only have a 40m wire here and could have done better with a beam but I guess my wire was better than the four original whip antennas on Sputnik although it had a distinct height advantage!"

Jim, W1PID, posted on QRP-L a log of the stations that he worked on the first day out. Jim was running 1w to a Windom antenna.
Date     UTC    Freq    Call         MY  HIS     Exchange
4 Oct  1220  21.061 PA0PJE   459 449   Netherlands  1/2W  
4 Oct  1243  21.059 DL3JIN     539 559   Germany Peter   
4 Oct  1255  21.062 UA4FCO  559 559   Yuri 5W  
4 Oct  1258  21.061 ON4ADR  559 579   3W  
4 Oct  1324  21.060 G3UYM/p  579 579  Cambridge Harold 5W  
4 Oct  1449  21.060 ON6WJ    579 569  Josef Sputnik 700mw  
4 Oct  1541  21.060 DL4VM    539 559   Saar Tom 5W  
4 Oct  1548  21.061 CO2KK    559 569  Arnie   
4 Oct  1557  21.059 PA0PJE   579 579   1W  
4 Oct  2012  21.064 WA5BDU 339 539   AR Nick   
4 Oct  2019  21.060 N0UR       559 579   MN Jim 5W  
4 Oct  2031  21.061 DL4CW   439 559   Joe   
4 Oct  2204  21.060 CT4RL/1 559 559   David 5W 
5 Oct 1244  21.060  UA1CEX  559 559  Vic 1w G5RV
Heard but NOT worked:
4 Oct  1220  21.061 G3VTT    Not worked
4 Oct  1312  21.060 IT9NMJ   Not worked
4 Oct  2028  21.061 K0ZK      Not worked was 559
I had some trouble with my homemade regenerodyne receiver for most of the first day due to a steadily increasing internal noise level. It eventually reached a level that made it impossible to continue. Contrary to the popular metaphor, real frogs will jump out of a slowly heated kettle well before they come to harm. I, on the other hand, apparently will put up with a slowly increasing noise level long enough to miss most of the stations calling me! In fact it only required 20 minutes to locate and correct the problem once I decided to act. The trouble stemmed from a noisy transistor in the regenerative IF amplifier/detector stage. Swapping this transistor with a spare solved the problem completely. I apologize to those stations who called, but failed to raise me on account of this issue. For example,
Peter/DJ0GD wrote to say

"Hello Mike ,at 1500Z I hrd ur call and dashes 539 also same at 1545z. I wkd DL3PB Sputnik 400 mW 549 but only 10 Miles away. I hrd him clg you later. Wkd UA4FCO but he sad was clg U but not heard."

Once my receiver problem was corrected the contacts came pouring in. Here's my contact log as of the end of the third day.

 Date  UTC   Call     MY  HIS  QTH    HIS STATION
4 Oct 1220  ON4ADR   519 559 Belgium     3w
4 Oct 1409   NN6T    559 569   AZ       ~1w
4 Oct 2027   N0UR    449 579   MN       5w to 3ele Yagi
5 Oct 1430   KA3P    539 569   FL     
5 Oct 1447  WB5BRD   449 589   AR       75w to Invee
5 Oct 1500  WA5TCZ   599 599   LA       50w to Yagi
5 Oct 1546  DL6HG    539 559  Germany   Sierra @ 1.5w
5 Oct 1619  SP7BCA   559 569  Poland     5w
5 Oct 1635  DL4HG    539 559  Germany   Sierra @ 1.5w
5 Oct 1639  DL6MN    529 569  Germany   
5 Oct 1713  DL3PB*   339 539  Germany   400mW Sputnik
5 Oct 1736  CT4RL/1  419 329  Portugal   5w
6 Oct 1827  AB9LM    559 559   IL            5w
6 Oct 1847  WA4SQM 569 579  GA
6 Oct 1934  DL4HG    549 559  Germany   Sierra @ 1.5w
6 Oct 1954  DF2OK    419 589  Germany    5w

The contact with DL3PB shown above doesn't actually count as a QSO, 
given that we lost contact with each other roughly one second before
he would have copied my report to him. Otherwise, we copied both
call signs and I copied Peter's report of my signal. While not technically
a QSO, any information exchanged between two stations located nearly 
6000km apart, both of which are running 400mW to simple wire
antennas, is bound to be a thrill. What's more, a receiver made from 
three germanium transistors  - all of which pre-date the 1957 Sputnik-1 
launch - was used on one end!

N0UR very kindly sent me an audio file of my 250mW Sputnik signal as
received in Minnesota (1642km distant) on the first day. Please click here 
to listen. Notice the little burst of "doppler shift" at the beginning of 
my transmissions ;o)

DF2OK surprised me with a recording of my 400mW Sputnik on 
6 October at ~20:00 UTC. Please click here to listen. All the way to 
Northern Germany...Vielen Danke Michael!

Shown below are some photos of the Sputnik QSO Party set up here at
AA1TJ. My receiver appears in the first photo. A crystal-controlled (24MHz)
converter built around a 2N128 surface-barrier transistor precedes a 
regenerative IF amplifier/detector made from a second 2N128 transistor. 
The detector is followed by an audio amplifier using a single 
2N109 vintage germanium transistor. The same 1.2Vdc supply used to heat 
the Soviet "Rod Tube" filaments is used to power this receiver.
  
My transmitter is appears in the next photo. The RF output power is 250 
to 400mW; depending on whether I use 57V or 72Vdc on the PA screen/anode.
 
The circuit board appearing in the foreground bears the transmitter keying
and R/T switching circuitry. A pair of modern, high-voltage transistors are 
used to key both the oscillator and the PA stages. A simple time-delay circuit 
applies a steady +57Vdc to the oscillator screen/anode as soon as the key is 
depressed. The DPDT relay activates at the same instant in order to switch 
the antenna and mute the receiver. Both the oscillator supply and the DPDT 
relay switch off a second, or so, after the key is released at the and of a 
transmission.
     
      
  

2 comments:

  1. TNX for Sputnik QSO Party!
    My TX only 3560 :(
    I d'not have rezonatore on 21060.
    http://ndb.at.ua
    US5EVD, Alex

    ReplyDelete
  2. You're very welcome, Alex!

    I had a wonderful time myself. I hope we can do it again next year.

    Until then, 73/72 and Gud DX!

    Mike, AA1TJ

    ReplyDelete