DIY Linear AMP

DIY-Amp.png

There are several versions of this Linear Amplifier on the net. They claim 100 Watts but in practice they are lucky to produce 70 watts and only after carefull fine tuning. Hear is the biggest killer of Amps. The optput is dirty they are require a multi band filter.

Make a 100 Watt linear amplifier from a kit:
https://www.qsoshack.com/make-a-45-watt-linear-amplifier/

[Top][Home]

Assembled-PA100

Assembled-PA100
Assembled-PA100
Assembled-PA100
"" Assembled-PA100


[Top][Home]

Filter Kit

ebay-filter-kit.png
Features:

[Top][Home]


[Top][Home]

DIY Kit 70w SSB Linear HF Power Amplifier Build

https://groups.io/g/BITX20/topic/76540689?p=Created,,,20,2,0,0

[Top][Home]
""

Videos

https://www.youtube.com/watch?v=a2PEWpgIoCY

https://youtu.be/CeegQYZ25J0

[Top][Home]

Hermes Lite 2 PA interfacing

There is no 5V on the HL2. Usually PAs provide a signal line which when grounded turns on the PA. This is what the HL2 does via the EXTPTT connector. The signal voltage can be up to 28V at 10s of mA. Is it possible to add a pullup on the XDT-PA70 side which the HL2 can pull low during TX? You may have to remove any optoisolator. Refer to the schematic of the xdt-pa70 unit?

If you really need 5V you will have to add a small regulator and level shifter. See

https://github.com/pressla/HL2_Extension_Jumper

https://github.com/softerhardware/Hermes-Lite2/wiki/IO#io-boards



[Top][Home]

References

Good discussion on some of the potential problems of build the PA and design of a 20 meter filter. https://pa-11019.blogspot.com/2016/11/diy-kits-70w-ssb-linear-hf-power.html

General theory of samll Linear Amps:
http://www.sm0vpo.altervista.org/tx/rf_pa_cct_00.htm

MiniPA-70 and MINIPA-100 step by step buils instructions:
https://ea8arx.blogspot.com/2018/06/minipa-70-step-by-step.html [Top][Home]
""
Glenn Lyons VK4PK
glenn@LyonsComputer.com.au
Ver:gnl20210817 - pre published v0.9