Wednesday, December 16, 2020

Sommerkamp TS-780DX touched up!

 Together with my radio friends Theo PA0KN and Edwin PA2LVD we saved a TS-780DX from scratch.

The Sommerkamp arrived from Belgium some weeks ago and had a few 🙃 flaws:

No audio on receive

No receive at all

No SSB transmit

Fault at 7 segment LED

Oscillating of PA after pressing ptt

Some knobs not original 

Case scratched and damaged.

We spend some time to fix these issues but after replacing the audio IC, a voltage regulator and zener diode, balance modulator, remove a short circuit in the IF part, repair cold joint at LED driver, put the PA in class A and perform some adjustments the transceiver came to live again!

Enclosure was also repainted and original knobs where placed.
Very nice to have a working 40 year old Sommerkamp saved from scrap!

The result (and yes it works on 10 meter band)

Sunday, December 13, 2020

Season’s Greetings

One of the strangest years ever ... let's hope 2021 saves us from all the misery! Happy holidays and stay healthy.

Friday, August 28, 2020

ATU-100 (N7DDC) automatic antenna tuner finished

 I finished this project with great craftsmanship of Theo PA0KN who made this enclosure, 

A very nice tuner kit from the far East!

Saturday, August 1, 2020

ATU-100 (N7DDC) Antenna tuner kit

Bought a nice kit (ebay / Ali, etc) to build an automatic antenna tuner (design N7DDC) which can handle approx 100 watts.
Tuner is usable from 160 meter till 6 meter.
It has a small but very clear oled display that shows all information you need.
For 30 euro i had the smd presoldered version, so the only thing you need to do is wind the coils and solder some normal components on the board.

Complete kit, very well packed in a plastic box.
PCB with all smd components already soldered.
You have to wind the coils yourself
Tuner finished! Next step is a nice enclosure

Sunday, April 19, 2020

UBITX Project

During this Covid-19 crisis the general advise is to stay at home.
Since i have a box full of unbuild projects i don’t have to bore and picked the UBITX to finish.
The Ubitx is an allband QRP hf transceiver and comes assembled for a very fair price.
I choose to upgrade to the Nextion touch display which includes a software upgrade for the Raduino.
There is a lot of information on the internet and also the new UBITX kit includes such a display.
For now i build the default kit and later on i will add a audio agc with a lm-317 audio ic.
My Ubitx with Nextion touch screen, build in progress

Saturday, February 8, 2020

Chinese CT-62 USB cat cable.

My original Yaesu CT-62 cat cable has a serial connector which is not very common nowaday.
So i ordered a Chinese clone for less than 6 euro incl shipping.
As soon as it arrived i decided to test this cat cable on my FT-817 and HamRadioDeluxe.
The cable was recognized on my Windows 10 pc, but it gave read errors while starting HRD.
So time for some measurements.... First open the USB connector and do this very careful to avoid dammage of the plastic enclosure.
You will see a small pcb with 3 wires and a uart ic.
With a multimeter i measured the mini din connector on the other side of the cable and concluded that the tx and rx wires on the small pcb where reversed...
Red and White wires are reversed soldered on the pcb

                                     This is how it should be! White wire is RX and Red wire is TX.
After changing the RX / TX wires the Chinese CT-62 cable works fine.

Yaesu FT-817ND battery replacement

Altough my FT-817 is not much used since i bought it new 10 years ago, the battery has lost it’s power and could not be fully charged anymore.
The original batterypack FNB-85 is quite expensive and due to the fact that i hardly operate on battery i decided to replace it by a third party battery as sold on ebay.
For less than 20 USD incl shipping you get this:

This Cameron Sino FNB85TW replaces the original pack and has the same dimension as the original battery.

Fits perfect. Charged and tested the FT-817 on battery power and it’s up and running again.