07 July 2023

Collins mechanical filters installation guide for Yaesu FT-8xx radios

Collins mechanical filters installation guide for Yaesu FT-8xx radios

Even although this line of radios is obsolete (except FT-818ND) there is still many of people who are looking for installation guide of the optional filters... 

1. Type of filter

526-8686-010: 455.00kHz centr. frequency / 0.45kHz BW @ -3dB / 2.00kHz BW @ -60dB / -5dB insertion loss / 7-poles  (simply 500Hz / 7-poles filter)

526-8686-030 (alias XF-115C): 455.00kHz centr. frequency / 0.5kHz BW @ -6dB / 2.00kHz BW @ -60dB / -5dB insertion loss / 7-poles  (simply 500Hz / 7-poles filter)

2. ESD protection

Install and use some ESD protection tools on bench like ESD mat grounded properly through 1.5MOhms resistor and wrist-band connected to the ESD mat at the corner.

2. Installation the filter (hardware)

For correct installation you can follow the manual for FT-817ND see page 74 (or respective FT-8xx version of radios).

Front panel view > slide into the socket while 3-pins are on the left and four pins are on the right side > filter case upwards. Push carefully on both sides at the same time to click into the headers.

Also you can check details here:
SP6AB radio blog: Home made CW YF-122C filter board for Yaesu FT-817/857/897

3. Filter board setup

Which filter is installed on the filter's PCB is defined by installed resistors combination.

If it is factory soldered, then do not care about it. 

If you installed yourself then check the proper resistors setup also on the link here:
SP6AB radio blog: Home made CW YF-122C filter board for Yaesu FT-817/857/897

4. Installation the filter (software) – Menu 38

After assembling the radio back and turning it on go to Menu 38 (long press F-button and turn the SEL knob on the left to position 38) and change the OP FILTER menu from OFF to CW in the middle row (by main dial knob). Then exit by long press F-button.

5. Activation the filter – NAR function

If all is ok and no ghostbusters in your radio, then now when you will short-press the F-button and using SEL knob you will find the IPO / ATT / NAR menu in third lowest row on the display > after pressing C-button (right under display) assigned to NAR function you should be able to select narrow filter for CW which is installed in radio. Also, it would be hearable by narrower and lower noise in speaker.

Note: For some reason some users are reporting that when trying to select CW position in Menu 38 there is only OFF and SSB... but after careful turning back and forth it should appear CW...

Hope it helps. 

73 - Petr, OK1RP
"Apple, Ten-Tec & Elecraft freak"

Installation document by P. Ourednik, 23-Jun-2023. Document 06-23, rev.1.0

25 April 2023

SBITX V2 - Hybrid SDR transceiver Part II. - Unboxing and installation

Sales of the SBITX V2 has been opened by HF Signals from 11-Apr-23 Monday morning. First units have been dispatched at around 19-Apr-23. I was really amazed how fast it went thru the continents as this unit was shipped on 19-Apr-23 and it arrived at my hands on 21-Apr-23 morning!

Well packed, labeled sn:0005 with signature from the person who was responsible for testing and packing all together. It looks cool and trusty.

There were not any issues with custom clearance using the DHL services just the VAT and DHL custom services fee had to be paid of course. 

The foams protecting the radio inside as same as the rest of accessories parts. Package includes radio, manual, packing list, mic, stereo jack3.5mm and 20cm of the power cable with XT60 power connector. This is now a common high amperage connector popular among the drone and r/c flyers. You will get a mating connector for this in your kit that can be soldered to any other kind of connector you may have on your power supply.

As the fully completed and tested radio has been ordered then the installation is easier and faster than in case of ordering unit without RASPi or even just assembled and tested transceiver PCB board.

After removing the radio from the box and plastic bag it is ready to plug in the power, antenna and run it. 

Attention: As it is not allowed to shipping electronics with batteries installed (in fact it is possible but special declaration and shipping conditions setup are needed and HF Signals did not manage that with DHL yet) please be note that your radio has not installed the RTC battery on the board. It is button cell CR 2032 type, and you will have to install it into the radio on arrival. (I will post some short article and pictorial how to do it soon)

After switching ON your radio and booting up the RASPi the desktop will appear in few seconds. Touch the sBitx icon to launch the radio itself.

The sBitx application will launch the browser. You will need to type in the passkey. The initial passkey is “123”. You can use the on-screen keyboard to type it in or use an attached physical keyboard then press Start.

Following the manual as a first-time user, you have to add some basic information to your radio. In fact, you can skip that step and add these information's any time later but as it is just callsign, your location grid you can do it now ...don't worry, it will happen :)

Btw: you can set up also the CW input (paddle, pump key or keyboard at this menu if you want)

Your radio is alive and together with the well-known screen you will hear the noise from the band.

Congrats! You are on the air with your new beast.

First test on the air with large beam here.

Open-source code and documents here. 

Manual can be download here.

Orders can be placed here.

73 - Petr, OK1RP


18 April 2023

Developer's Edition (DE) SBITX V1 - Bake oven?

The new SBITX V2 is the successor to the previous prototype version SBITX V1, which was only available in limited quantities as a development prototype marked "DE" (Developer's Edition). 

It featured a larger, compact case, a flat-mounted transceiver board, and a heatsink on the outside back.
And why do some like to call the SBITX V1_DE as a microwave oven or ham radio version of the bake oven? Judge for yourself... :)

Many owners quite liked the cabinet, and the nickname could have been adopted if the new SBITX V2 version had not brought design changes in addition of the changes on transceiver board. The depth of the cabinet is now one-third, transceiver board is located on the back and the new look of the housing is more reminiscent of a door opener...

73 - Petr, OK1RP

13 April 2023

SBITX V2 - Hybrid SDR transceiver Part I. - Intro

The low budget 40W High Performance Hybrid SDR transceiver for the geeks, tinkers but also for DXers and field operators ...it is the new SBITX V2.

The SBITX V2 is an open source, low budget, high performance Hybrid SDR for the 21st century radio amateurs by HF Signals Co. Powered by an internal Raspberry Pi 4, it has CW/RTTY/PSK31/SSB and other digi modes with logging software, macros, spotting in-built.

- Big & compact: Although compact, it has the largest display shipped with a transceiver, a capacitive, touch screen of 7 inches.

- All software to run modes like RTTY, PSK31 is integrated into the radio, without any messy configurations, setup, etc. to deal with.

- It switches soundlessly from transmit to receive and between bands due to its electronic of filters and T/R switching.

- Band-stacking VFOs with 4 memories on each of the 8 bands, 9 convolution digital filters for the best audio experience.

- High performance electronics with a passive-FET front end, 8 crystals’ filter and a low phase noise, temperature compensated crystal oscillator.

- The built-in, editable macros that make it a breeze to work DX or compete in contests.

- Add an HDMI monitor or use the browser from your PC/tablet to have a large screen experience of all the features of this amazing radio.

- The SBITX V2 will neatly slip into your backpack with its compact, slim size of 10 inches x 6 inches x 2 inches and weight of under 4 pounds (less than 2 KGs) with room to spare. With its 40W transmit output, it is the most powerful radio you can put into your backpack.

- It is armed with an XT60 power connector that you can use with lightweight 3S LiPo batteries to provide hours of field operation (The receive current is 600mA, the transmit current can go up to 8A depending upon the drive settings).

- The built-in mic and the on-screen keyboard, macros make it easy to operate all modes, voice/digital or CW without a key, mic or an extra computer in the field.

- It has an accurate real-time clock to time digi transmissions and log the contacts made.

- The built-in logger eliminates the need to carry the logbook too.

Low budget & High performance radio

- Bulletproof hybrid superheterodyne with passive-FET KISS mixer

- Brick wall crystal filter with 8 crystals

- 80dB close-in dynamic range, 90dB wide dynamic range

- Low phase-noise, temperature compensated reference oscillator

- 30-40W output on all bands from 80m to 10m

- Transmit IMDR of 30dB (from PEP levels)

- Silent, fan-less operation

- Noise-less electronic T/R and band switching

- In-built 2-tone transmitter to tune the antenna and measure IMD

CW/RTTY/PSK31 with logging and Macros

- Totally noise-less, fast electronic T/R without noisy relays

- In-built N1MM style Macros support Running and S&P

- Uses Fldigi with its high-performance decoder in the background

- Raised cosine CW keying with perfect shaping

- 9 Ring-free Convolution filters from 100Hz to 3kHz

- Use the on-screen touch keyboard or add a USB / Wireless keyboard for effortless CW sending if needed

Logger and Logbook

The SBITX V2 has a logger and logbook with RDMS support. N1MM style logger with macros and automatic logging of contacts with the frequency, mode, time automatically filled in. Use macros on CW / RTTY / PSK to send out standard messages with the press of a button / key if needed.


See the spots, DX clusters on the radio with in-built telnet to DX Clusters, Reverse Beacon, PSK Reporter, etc.

Hackable code, skinnable GUI

Full source code, circuit and explanations on github.com/afarhan/sbitx

Write custom apps in JavaScript without learning SDR coding.
Open source, hackable SDR written in C.
Develop your own skins and UI in HTML/CSS/JavaScript.
More modes and functions planned.

Access and operate your SBITX V2 over the home Wifi

With your SBITX V2 connected to the home Wifi, just open http://sbitx.local on the browser of your phone/tab/pc and start operating your radio! With the bigger screen of your PC or tablet, you can have an expanded user interface of the SBITX V2.

Accessibility & Command line support

The SBITX V2 project is committed to providing eye-free usage for the SBITX V2. As a first step, this release features a command line interface that provides all the features of the GUI.

Brief Specifications

Well, it is a different approach to the GUI user interface, and the radio as same as the software itself is still under development and improvement. S
o, we expect some bumps on the road for early adopters. However, having a large 7 inches screen and RPi on board will make this a fine radio to use in the shack.

Anyway, it is an interesting project. Time will tell, how the radio works and if it proves itself in practical operation on the bands.


HF Signals was founded by Ashhar Farhan, VU2ESE. HF Signals Co. is based out of Illinois, located at 44W, Doral Drive Apt 202, Glendale Heights, IL 60139, USA.

HF Signals manufactures all radios in Hyderabad, India and they works with a collective of workers. Each of the toroids is hand wound in India. This provides these working women with a livelihood. The assembled boards are then DC checked.  A final RF check and tune-up is performed to check the receiver’s sensitivity as well as transmitter’s output before being shipped. Each board is individually numbered and signed by a radio ham who tests them for performance before they are shipped.

There is an active and very informative forum for learning and getting help that is entirely driven by the builder community. Join the group on https://groups.io/g/bitx20


73 - Petr, OK1RP

07 March 2023

RGO ONE 5th production lot info by Boris, LZ2JR

Since all radios from 4th production lot are completely sold, Boris, LZ2JR posted PREORDER form for 5th production lot radios.

Possible sale start period is June 2023.

Please fill in your RGO ONE order here.

73 - Petr, OK1RP

10 January 2023

RGO ONE Audio Filter functionality - firmware 2.50b available

New firmware version ver.2.50b is available now in download section which reveals use of a new AF optional board – digital DSP audio filter board. Ver.2.50b is first step to the new DSP features of the radio. With new Ver.2.50b radio detects AF board and set it in bypass mode.

Next FW updates will add some basic functions like digital filters in CW/SSB, audio peak filter, CW tune and other…

Download 2.50b here.

10 October 2022

Plastic injection mould for RGO ONE knobs ready

News from Boris, LZ2JR and his Mission RGO One crew dated 10Oct 2022...


I am very excited to share with all friends that we just finished tests of our new plastic mould for RGO ONE knob sets. Making this was very very long time and cost consuming process but finally we are ready and first knobs were shot by the machine finished and ready to go…

Have a look at pictures:

Main dial knob still needs some parts to be finished but little knobs are all ready to go. Every stroke of the machine produces 7 parts - main dial knob cap, finger dimple, encoder knobs - 3pcs., concentric pot knobs 2pcs.
3-D printed knobs you use on your RGO ONE will be no more available.

73 es GL
Boris LZ2JR/AC9IJ"