Search found 996 matches

by Daniel Wee
Thu 11 Nov 11 2021 1:03 am
Forum: Radios
Topic: SunSDR2DX
Replies: 5
Views: 21757

Re: SunSDR2DX

TCI to CAT (ICOM, Yaesu or Kenwood) bridge using ESP32

https://iw7dmh.jimdofree.com/sunsdr2-pr ... libraries/
by Daniel Wee
Wed 10 Nov 10 2021 11:39 pm
Forum: Radios
Topic: SunSDR2DX
Replies: 5
Views: 21757

SunSDR2DX

SunSDR2DX to SPE 1.3K-FA cable In our cable the PC817 optocoupler is flipped upside down to get the pins in a matching orientation. The pins have been bent up. The SPE supposedly requires only a 2mA current rating so the PC817 should be okay (nominal 5mA). There is a 620-ohm resistor in series with ...
by Daniel Wee
Fri 05 Nov 05 2021 9:29 am
Forum: General Discussions
Topic: Packet Radio (AX.25)
Replies: 14
Views: 26928

Re: Packet Radio (AX.25)

For the digipeater, check pi@ port 60023

Use "screen -r" to reattach to the screen, and "ctrl-A" followed by "D" to detach.
by Daniel Wee
Mon 11 Oct 11 2021 1:13 am
Forum: Radios
Topic: Kenwood TM-V71A
Replies: 3
Views: 11271

Re: Kenwood TM-V71A

Packet levels On our implementation, with the notch on the top and looking into the connector from the 1-o'clock position clockwise:- 1. PR1 from the radio into the TNC 2. PKS - PTT keying 3. output from the TNC to the radio PKD (calibrated for an output of 40mV p-p) 4. Ground to radio DE The outpu...
by Daniel Wee
Sat 09 Oct 09 2021 8:18 pm
Forum: Radios
Topic: Kenwood TM-V71A
Replies: 3
Views: 11271

Re: Kenwood TM-V71A

Second digipeater hardware

1. Vention USB soundcard (Challenger SGD10)
2. Raspberry Pi 4 8GB
3. PR1 and PKD pass through 1:1 Bourne audio transformer with 10uF on radio side
4. GPIO 18 as PTT
5. GPIO 23 as DCD
by Daniel Wee
Sat 09 Oct 09 2021 3:24 pm
Forum: General Discussions
Topic: Packet Radio (AX.25)
Replies: 14
Views: 26928

Re: Packet Radio (AX.25)

For a guide to installing Direwolf on the Raspberry Pi 4

http://hb1bbs.com/Raspberry-Setup/

Note that in order to get SSH running on headless set ups - you will need to create a file called "SSH" in the boot directory.
by Daniel Wee
Sat 09 Oct 09 2021 12:19 am
Forum: Radios
Topic: Kenwood TM-V71A
Replies: 3
Views: 11271

Re: Kenwood TM-V71A

by Daniel Wee
Thu 07 Oct 07 2021 8:44 pm
Forum: General Discussions
Topic: SARTS Repeaters
Replies: 53
Views: 376246

Re: SARTS Repeaters

Retuning Telewave TPRD-1544 for second repeater (145.075/145.675MHz)

RXANT4.png
RXANT4.png (15.19 KiB) Viewed 88934 times
TXANT4.png
TXANT4.png (14.89 KiB) Viewed 88934 times
TXSWR4.png
TXSWR4.png (16.76 KiB) Viewed 88934 times
TXRX4.png
TXRX4.png (14.63 KiB) Viewed 88934 times

Final results:
TX insertion loss = 1.24dB
RX insertion loss = 2.87dB
TX-RX isolation @145.675MHz = 84.43dB
TX-RX isolation @145.075MHz = 73.44dB
TX SWR = 1.31