7159 kc dc receiver

               Here is the foto of my finished receiver assembled during Diwali holidays.  All modules and box was made earlier. I assembled it or to be exact reassembled individual modules made earlier for different project. Put. A xtal qrp tx on 1/4 wire antenna. (for this transmitter see this post :- https://vu3inj.blogspot.com/2014/12/7159kc-beacon-cw-tx.html ) .
receiver sounds good. Tested enough. Now need to increase tx power and see whether i can be received on 7159 kc xtal around 100km ?

i am putting the front end band-pass filter to load external antennas. its a very standard design i used with my other 40 meter xtal receivers.

er

Here is fotos of test transmitter.

The cave Radios.

I had the nightmares last week, because i was also praying to save the Thia footfall team 11players+1 coach stuck into the cave. IT was a very daunthing task to save them. They have into there already 14 days/2weeks without any proper food, sunlight , information. It was the coaches budhist monk training that helped them keeping togather as a group. They silently sat there and waited for their search.
Thialand is not india. It has budhist rule and they value human being. India has secular view points. Even in rescue we think in terms of caste !

But any way. This incident has something to do with the HAM Radio. How they were able to communicate to the surface and other cave rescue team.

The British team had brougth along with them the cave radios. These cave radios operate on the very low frequency. there are atleast three types of radios in use now. hyphone, tesla, etc. there is difference in the range depending on the type of antennas on use. whethere you use loop 1 meter or a big tail antenna of 15-20 meter. hi hi we have good lenght of wire at the cave. other freq are not able to span the distance of cave rock. so CB or any VHF could not be used. So, we have to design something. our G3TDZ had done very interesting designs.

They use down converter for cb radio. usb only as the power is very  precisious at the cave.

 i think i should try one crystal based design 5ok and test in on my farm. will tell ya.

DDS VFO

        At last the the Dev Guru VU2DEV broke my hurdle and gifted me a working DDS VFO make by the great kerala om Saji VU3WIJ. I am thankful for that DDS VFO. it goes from 11 Mhz to 25 Mhz.   THANK YOU VU2DEV.

on air

cw/dsb 14318kc xtal 15w
cw/dsb 7159kc xtal     5-7w

give me RST

xtls filters

bacterias

/*i made these codes years ago, its innocent one. it creates 9 files each size of 200mb. have funn. compile , run it..........*/



/*file name is bacteria.c first generation*/
/*This programe is for :-         */
#include<stdio.h>
#include<conio.h>
#define ASK(prompt,response) puts(prompt); gets(response)

main()
{
int i,k;
int n,m;
char *ab[26]={"Aajka","beipea","cepakeo","deiiei","eakpqmve","fipqvhq","guran vopq","opwqffwih","qwneryiri","fwkleopj","kokqwpo2n","867qwqkj l",
            " q wl4j58635we; kl;qkqw23u4p45m","QQ3P[Q3P42\14"
            ,"QOWQI0o","pRIR3QW2787A","qAQ2O4VK558902%*)","rRIW[PQ","IWQIOs","quq  t","CJWEIu","riq[v","weo578****","#@%&^$#@x","%*()+!@#$$~!y","z" };
char *abc[26]={"a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"};
char *NUM[10]={"1","2","3","4","5","6","7","8","9","10"};
char another;
FILE *fp;

for(m=0;m<9;m++)
{
char FNAM[25]={""};
strcpy(FNAM,"Aveseq");
strcat(FNAM,NUM[m]);
strcat(FNAM,".dat");
fp=fopen(FNAM,"wb");   
do{
for(i=0;i<3200;i++)
{
    fprintf(fp,"%d",i);
    for (k=0;k<25;k++)
    {
    fprintf(fp,"%s",abc[k]);
    fprintf(fp,"%s",ab[k]);
    };
}
fseek(fp,0l,2);
n=ftell(fp);
}while(ftell(fp)<200000000);
fclose(fp);
};
}

VHF BOOSTER OF CATV

For long tome i wanted to see what is inside the analogue VHF cable tv booster amplifies.They were in great demands before the digital system kicked in.
The start of the VHF broadcast TV started around 1980 as home to home a 3 hour picture programe. The cable guy has the VCR and he connected the cable. That cable brought the single chanel and we sat and saw the TV. It was particularly aimed at the house-wives and childrens. The small players mush-roomed.

Then next stage was the day and night time pictures. This was a monthly rental.

This developed with multiplayer/providers in a single city. Then came the satellite TV channels and permanent studio environments. It removed the small time players and now a single entity of the providers grew like a monopoly.

Then came the paid channel concepts and presto the industry was born. The variety of digital and analogue, free and paid channel setup came, big dish. Then ISRO also jumped in with its new technology and it was the breakthrough.

At this time the cable net work developed in its entirely depending on the big studio where multiple saterlite dish antenna and receivers were housed and from there all the city was covered. At this time this VHF boosters were used.

Suddenly the satelites channel become paid, it become digital and cabling was changed from lowly RG58 to higher quality one.  TV become multichanel. 500 tv chanel, vhf-uhf-shf. And that's it.

Those TV booster become obsolete. In the EU peoples used the satelite receiver as AMTV receivers for their 10GHZ (?)band etc. But, we do not see anything of that sort here in india. peoples do not move nor reached to VHF.

Anyway i bought the box for its box values. I will tear it down and house a small QRP receiver/transcever  for my portable single freq use.

oh yeh, i got BFW15a and c2725 and 7 ferrites beads. i bought it for only 1 $ (Rs100/-) .

Till than folks let me work, then talk......