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Reviews Categories | Microphone Equalizers & Transmit Audio Accessories | Drake SP-75 external true RF clipping speech proc. Help

Reviews Summary for Drake SP-75 external true RF clipping speech proc.
Drake SP-75 external true RF clipping speech proc. Reviews: 1 Average rating: 5.0/5 MSRP: $$200-ebay
Description: A TRUE RF speech proc for any rig.
Product is in production.
More info: http://
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WA2JJH Rating: 5/5 Mar 14, 2004 09:33 Send this review to a friend
A great external RF speech proc.  Time owned: 3 to 6 months
The years when I could not run an AMP, I always thought a good speech proc. would give me a chance with the kilowatt crowd.

The answer can be no, marginal or yes!
Never like audio compression. You get every sound in the shack!

The idea is to bring increase the RF envelope and the rigs average power to be closer to the peak envelope power.

Every rig that I owned had the RF PROC built into the rig. It can be done externaly!

I am not going to go into all the technical details. See the Drake pages.

You mic input is mixed with a local oscillator RF signal, then filtered with 2 ceramic filters to get a CLEAN SSB signal. The SSB signal is amplified then RF clipped. The RF processed signal goes through another ceramic filter to shape and clean the highly processed SSB.

Only a simple ceramic filter has to be used to make the signal squeakly clean. This is because the SSB signal is then converted back to audio.

The added bonus is a noise gate. when your not talking the audio is attenuated by 20 db.

This means you can use your VOX with this PROC.

If you want to see how true RF clipping speech processing will make you stand out CLEANLY, check out ebay! Forget the AUDIO DSP PROC in you rig.

You will see up up a 4 fold increase(20db) in average power(do not use more than 10db, your finals may only handle 2-3 fold increase), without ANY extra background noise.

There are pots for rig and mic matching as well.
This was designed for the Drake TR-7/T-4 rigs. You will have to do a simple mod. to power this most excellent speech processor.


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