Izbornik Zatvoriti

Iron Powder Toroid Cores Color Codes

Skraćena veza: https://pedja.supurovic.net/veza/8352

Iron Powder Toroid Cores part numbers are presented using format Tddd-m where dd is core diameter in tenths of inch and m is material grade. Also, cores are color coded to represent material grade.

Material grade defines frequency range core may be used for. There is no strict standard for coding but for informal purpose this table can be used.

Color Frequency
0 Tan/Tan 50 MHz – 350 MHz
1 Blue/Clear 150 kHz – 3 MHz
2 Red/Clear 250 kHz – 10 Mhz
3 Gray/Clear 20 kHz – 1 MHz
4 Blue/White 3 MHz – 40 MHz
6 Yellow /Clear 3 MHz – 40 MHz
7 White/Clear 1 MHz – 25 MHz
8 Orange/Clear 20 kHz – 1 MHz
10 Black/Clear 15 MHz – 100 MHz
12 Green/White 30 MHz – 250 MHz
15 Red/White 150 kHz – 3 MHz
17 Blue/Yellow 20 MHz – 200 MHz
42 Blue/Red 30 kHz – 80 kHz


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LCD ESR tester – multimetar

Skraćena veza: https://pedja.supurovic.net/veza/8105


Zamislite da možete da imate univerzalnim merni instrument koji meri sve: otpornost, kapacitet, induktivtet, diode (obične i zener), tranzistore (bipolarne, FET, MOSFET, JFET), tiristore…

Otiđite u maštariji još dalje: zar ne bi bilo sjajno da ne morate uopšte da se cimate nego prosto ubodete komponentu u instrument a on sam prepozna šta ste uboli i izmeri karakteristike?

I povrh svega, da to lepo pregledno prikaže na ekranu?

Luda ideja, ali još je luđe da to u stvari postoji i to čak radi i više nego što ste izmaštali. A najluđe je što je vrlo jeftino. Ovakav tester košta oko 15 do 20 dolara, a meri maltene sve što ubodete u njega. […]
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APRS/Packet Radio audio cable for connecting Kenwood/Baofeng/Wouxun to Samsung SIII

Skraćena veza: https://pedja.supurovic.net/veza/7662

Here is a schematics of audio cable connecting Samsung SIII to Kenwood/Baofeng/Wouxun or other compatible radio.


Samsung SIII uses four pin 3.5 mm TRRX connector that differs than standard TRRX.

This cable can be used for APRS/Packet Radio. Most popular program for this purpose is APRSDroid. ALso can be used for Echolink, audio recordings, or similar usage.

You have to adjust volume output on both Samsung phone and radio to avoid distortions. Cell phone cannot control PTT of radio so you have to turn on VOX on radio to enable triggering TX when signal should be transmitted.

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Remote Controlled Antenna Switch

Skraćena veza: https://pedja.supurovic.net/veza/7497

As I live in apartment building I have apparent problem with setting up ham radio antenna. The obvious place to set up antenna was the roof as it  is easily accessible. Due to small space and me not wanting to make mess of a wires, I decided to use compromise vertical multiband. A friend had spare DunaX-GPN4B (40, 20, 15 and 10m) so it was obvious choice. I had to put down about 30m of coax cable to my apartment, and soon I was in the air.

Not for long I found out that I do miss 80 meter band a lot. […]
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Universal CAT and programming USB to RS232 TTL interface for ham radio

Skraćena veza: https://pedja.supurovic.net/veza/7437

As soon as I got first two ham radio rigs, I needed to connect them both to PC, to program memories or use CAT control from logging software. I realized that it is impractical to have as many USB to RS323 adapters as rigs.

As serial connection for radio requires just RX, TX and GND lines, and it is the same for most of modern radio stations. It is actually only radio connector that is different – signaling is the same.

It showed up quite easy to build simple multirig adapter. All you need to do is to use existing USB to serial interface adapter, cut it’s cable in two and insert male and female three pin 3.5 mm jack (commonly used as stereo audio connectors). […]
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