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> Mini-circuits miqa-91 i&q quad modulator 90MHZ (qty.3)
Mini-circuits miqa-91 i&q quad modulator 90MHZ (qty.3)
Mini-Circuits MIQA-91 I&Q Modulator 90MHz (Qty.3)
On offer are 3 new (old stock) pieces of the Mini-Circuits MIQA-91-3. One here for the ham experimenter!
Getting a good 90 degree hybrid, mixers and combiner is the harder part of building a phasing SSB transmitter. These cans contain all of those parts in one professional high performance assembly.
They provide excellent rejection of carrier, opposite sideband and harmonics (which are generally 40-50dB down, see datasheet).
It struck me that these could form the heart of a neat little SSB exciter, using a 90 degree audio phase splitter (like the one in 'Experimental Methods'*) to drive the I & Q inputs, and a 90MHz LO input, perhaps from a doubled 45MHz resonator. The resulting signal would then be mixed with a VFO. A VFO range of 54 .. 88.2MHz would give 144-148MHz mixing up, or 1.8 - 30MHz mixing down. The exciter would thus cover ham HF and 2m VHF bands.
Still, at this stage it's an untried idea, and not at the top of the to-do list. (BUT ... I'll send an extra set of these MCL parts to the first person who gives it a go and let's me know! ;-)
* Experimental Methods in RF Design - Wes Hayward, Rick Campbell and Bob Larkin
Other possible uses are as a digital TV exciter or similar ...
http:// /pdfs/MIQA-91M.pdf
