Took a quick look at F-26 service manual and schematic.
#1 The 75 ohm input feeds the front end transformer directly. The 300 ohm input goes through extra balun first.
#2 The instructions do not indicate any high blend action resulting from use of the muting and stereo threshold controls. (I do not believe there is any auto-blend either, since I hear very clearly the KPAC buzz which is quickly erased by using the high blend control on the Kenwood KT-6040.)
#3 The front end has two mosfet amps. First there is double tuned filter, then mosfet amp, then a quad-tuned filter (!?) then another mosfet amp, then another filter before going to mixer. I think the quad-tuned filter may be partly controlled by the locking circuit. The filter-amp-filter-amp-filter-mixer topology has been declared "optimal" by my friend T. There are two tuner gangs used in the oscillator, (the second being oscillator filter?) another optimal approach.
#4 The IM and Spurious rejection ratios are 120dB. You won't find numbers like that for any varactor tuned tuner. I am coming more to believe these are the important specs...they indicate how well a tuner is cleanly pulling the needle out of the RF haystack. Noise figures from bench testing are unrealistic as there is no RF haystack in such tests. Especially now, when the radio frequencies are saturated with stuff.
#1 The 75 ohm input feeds the front end transformer directly. The 300 ohm input goes through extra balun first.
#2 The instructions do not indicate any high blend action resulting from use of the muting and stereo threshold controls. (I do not believe there is any auto-blend either, since I hear very clearly the KPAC buzz which is quickly erased by using the high blend control on the Kenwood KT-6040.)
#3 The front end has two mosfet amps. First there is double tuned filter, then mosfet amp, then a quad-tuned filter (!?) then another mosfet amp, then another filter before going to mixer. I think the quad-tuned filter may be partly controlled by the locking circuit. The filter-amp-filter-amp-filter-mixer topology has been declared "optimal" by my friend T. There are two tuner gangs used in the oscillator, (the second being oscillator filter?) another optimal approach.
#4 The IM and Spurious rejection ratios are 120dB. You won't find numbers like that for any varactor tuned tuner. I am coming more to believe these are the important specs...they indicate how well a tuner is cleanly pulling the needle out of the RF haystack. Noise figures from bench testing are unrealistic as there is no RF haystack in such tests. Especially now, when the radio frequencies are saturated with stuff.
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