Main Board (MB)

RGO ONE Main Board (MB) or so called mother board fits all connectors on the rear panel, power supply, I/O controller (second CPU). MB is also intended to be a chassis for all RF boards and options, as long as “cable harness” and board interconnections.
The board has the following components on it:
– I/O micro controller U5, DAC U7, external fan control – U8, T12, signal multiplexer U9, 3.3V LDO regulator chip U4

– USB FTDI chip F1

– I/O connectors at the back side, daughter board connectors, power on/off switch, level converters, 5V,8V LDO regulators

PCB component side (bottom):

PCB component side (bottom) values:

PCB top:

LO board

LO board provides all oscillator signals needed for signal conversion and mixing. The board consists of the following components:

– LO first oscillator realized by U2 – SI570 (570CAC000141DG), 3 switchable low pass filters: 10.8-15MHz; 15-24MHz; 24-39MHz. Filter switching is performed by I2C chip PCA9536
– 9MHz generators – U3 (SI5351) BFO, CW sidetone, beeps, U1 (SA-612) balanced mixer which acts as CW/SSB monitor product detector, digital poteniometer – U7 (MCP4018-502E)
– Tone shaping, (tones on/off ) circuitry – T1,T2,T5
– Temperature compensation oven made by thermo resistor R14 and T3,T4

PCB component side


In order to achieve good results with low harmonic content and stability – PCB board is well shielded in two component metal tin can:



RX MIXER standard is ADE-1 diode ring mixer. Here described is optional high dynamic range H-mode mixer.

The schematic and original H-mode mixer concept has been designed by Colin Horrabin G3SBI and further developed by Martein Bakker PA3AKE.

PCB component side


RF MIXER board does all RX/TX signals on IF and operation frequencies.
On receive the signal comes on CX3 coaxial connector, then passes (or not) through input attenuator R10,R13,R14, then via switches come to BPF board. IF TRAP circuitry consists of L1, C7, C38. Then signal passes through U3 (ERA6SM) RX preamplifier (operator switchable). RX MIXER is on additional subboard and sits over RF MIXER board. 9MHz diplexer follows and then IF amplifier – U12 (ERA6SM). After some switching and attenuation signal comes to the first crystal filter – 2.7kHz then to CX6 coaxial connector and IF/AF board.

On transmit the signal from SSB GEN board through CX7 connector passes through crystal filter and after TX/RX switch to a pin diode D1 attenuator. It is driven by ALC circuitry performed by U16 and T4.
U11 is TX mixer which is fine balanced by R62 and impedance matched by L10,L18 wide band transformers. Output mixed signals are further filtered by BPF board and amplified by U3 and U9. Output attenuator R4,R5,R6 is following then via CX4 signal goes to linear amplifier PA55W board.

Component side PCB

Component side values

RGO ONE Power amplifier module

Power amplifier building process:

Power amplifier consist of two sandwich nested printed circuit boards – PA linear 55W board and low pass filter module.

LO /local oscillator/ BFO tones board

Here is some pictures of LO board – ready and shielded

Copper straps are added in order to improve ground on the board

RGO ONE building process

By now all printed circuit boards are ready and populated. We have also some boards – completely tested and aligned:
1. IF/AF board
2. RF MIXER board
3. LO/tones board.
4. Front panel assembly – CPU, LCD/switches boards
5. Both crystal filters – 2,7kHz and the optional 4 pole variable filter

Still working on back panel module – PA and LPF. BPF,SSBGEN are being carefully tested on the bench

Go Go Go … RGO ONE

Today we made continuity and DC test of the front panel assembly consisting of:
CPU board
LCD&switch board

All tests passed OK and tomorrow face panel’s CPU will be flashed for the first time

Building first lot of 10 RGO’s

We recently received first ten sets of printed circuit boards for RGO ONE HF transceiver.
So till today we managed to populate some of the boards. Rgo one consist of 20 pcb’s … so a lot of work lies ahead.
LCD&switchboard – finished:

LCD&switch board component side:

IF/AF (intermediate 9MHz frequency – audio frequency) board

RGO ONE in LZ DX contest

Search and pounce in LZ DX contest with RGO ONE. Testing new features – DTR/RTS keying from N1MM contest logger; Testing temperature management with new FAN cradle.



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