QEI 690 Mod Monitor issue

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musiconradio.com
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QEI 690 Mod Monitor issue

Post by musiconradio.com »

I have a QEI mod monitor in the studio. It is just "Eye candy" I don't care about calibration.

#1 any suggestions on how to inject more signal thru the antenna input.

#2 the LO unlock is now on. Meters are pegged. has it finally bit the dust?

Kelly
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Joined: Thu Aug 21, 2008 5:32 pm
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Re: QEI 690 Mod Monitor issue

Post by Kelly »

The electrolytic capacitors in the IF board have probably dried out. May have to just shotgun all the caps.
QEI always used the cheapest components with all their products. The fact that monitor has run this long is unusual.
Skype:kellyalford Twitter: @KellyAlford

musiconradio.com
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Location: Livingston Alabama
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Re: QEI 690 Mod Monitor issue

Post by musiconradio.com »

Thank you.

kcbooboo
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Re: QEI 690 Mod Monitor issue

Post by kcbooboo »

You need to get the LO Unlock LED extinguished before much else will work. The frequency synthesizer is needed to mix with the incoming signal so it can be demodulated and drive the meters. There's likely more stuff at fault too. At least there isn't a microprocessor in the unit.

Start with the power supply then work your way towards other failed areas. That unit should be repairable if you're willing to spend the time doing it. A manual is floating around on the web. The only difficult parts to obtain will be those made by QEI or some of the older ICs, but the rest should be common components.

Bob M.

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