PCBs are still available... If you need this, please... do not hesitate to contact me. Just email: sq7bfs@qrz.pl
If you need more ?? I have also KITs...




*** *** *** *** ***


This PA2 OMEGA is very simple HF (1.8 to 30MHz) amplifier. The maximum power is up to 20W for whole range of frequency. This amplifier requires 0,5Vpp of clear input signal. It have been designed for OMEGA transceiver (by SP7NJR - more...) but you can use it with any other TRX, which has a correct output signal level.
The amplifier consists three main parts:
- Pre-amplifier based on S868 integrated HF amplifier
- Driver based on 2SC2314 transistor
- PA with two RD16HHF1 transistors

Schema of PA2 OMEGA (here...)
The PCB of PA2 OMEGA is presented in picture below.



PCB assembling view:

Setting of quiescent currents

1.Connect 50ohm load
2.Do not connect any signal to input of amplifier
3.RRP1, RRP2, RRP3 set to minimum
4.Install Iq3 and Iq4 jumpers
5.Do not install Isp2 jumper
6.Connect mA meter instead Isp1 jumper
7.Turn ON power supply
8.Set 25mA of T2 quiescent current (with RRP1)
9.Turn OFF power supply
10.Disconnect mA meter
11.Do not install Isp1 jumper
12.Connect A meter instead Isp2 jumper
13.Set 480mA of T3 quiescent current (with RRP2)
14.Set 960mA of PA (T3+T4) quiescent current (with RRP3)
15.Turn OFF power supply
16.Disconnect A meter
17.Install Isp1 and Isp2 jumpers
18.Ready to use

PCBs are still available... If you need this, please... do not hesitate to contact me. Just email: sq7bfs@qrz.pl
If you need more ?? I have also KITs...

A little PCB upgrade...

You have to cut the path between T2 emitter and elements R7,C9*. Place the R7_ (2,2om) resistor on the path.

Power measurements

80m band
- 0,5Vpp input signal
- 50ohm load
- 92,8Vpp output = 21,5W



10m band
- 0,5Vpp input signal
- 50ohm load
- 90,4Vpp output = 20,4W