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March 25, 2024. MMIC Amplifiers

Yet another tool for your tool kit ~ The MMIC (Monolithic Microwave Integrated Circuit) Amplifier. The MMIC amplifiers are simply superb when looking for a module to add 20dB gain to a circuit, are termination insensitive, 50 Ohms in/out and low noise figure and good to 2GHz. 

I first used MMIC amps in a bilateral 20M SSB Transceiver way back in 2010 and while it didn't make the cover of Rolling Stone it did make the cover of QRP Quarterly.

 

By far the biggest hurdle with using MMIC amplifiers is that they are surface mount and really small. They are incompatible with glue down Manhattan pads, Fat Fingers and require steady hands. Careful circuit layout is also a must!

 

 

12 Sq In. and 50% of a SSB Transceiver, A steered module with IF, PD/BM, Rx/Tx Mixer




My AG393-86G MMIC Amplifier


The devices you see above are Tri-Quint AG303-86G's which are now obsolete. BUT Mini-Circuits sells the MAR-6SM+ which is DC to 2GHz, with 20dB gain and a 2.3 dB Noise Figure with an application circuit shown below. For less than $20 you can buy 10 units at Digi-Key.

The MAR-6SM+ operates with 3.5 VDC but the table shows the dropping resistor needed for various voltages. The Mini-Circuit devices draw about 16ma. I used a 1uH choke with the Tri-Quint devices and the caps are 20nF. The supply voltage on my application was 5VDC.





Aside from that 1st project in 2011 I have used MMIC devices in several SSB Transceivers especially where space and performance were a concern.

MMIC's are for the more advanced homebrewer since they are SMD and are way beyond the Ugly or Manhattan style of construction. But then again, their specifications and SMD size suggest a perfect balance for a minimalist yet feature packed radio. 

The MMIC 20M SSB on the Cover of QRP Quarterly!


Yet another tool for your kit.

73's 
Pete N6QW

PS I have been collecting some important topic data. It appears the blog readers are focused on simple project style posts and bypass anything Raspberry Pi or digital communications modes. I got the message!



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