Recently got this amplifier for a steal ($10), I see no maker marks, call signs, or other digits etched into the PCB.
Does anyone recognize this pcb as part of a kit?
[photo="medium"]4362[/photo] .
I think this could be used for 70 cm / Amateur TV reading the MRF646 datasheet.
[photo="medium"]4361[/photo] .
I know nothing of amplifier design but this amp can help me grasp the basics by giving me a physical layout to analyze/study. Do you see a bias circuit, because I do not, all I see are two trimmer caps on the output and two on the input, but no thermal tracking diodes; if this was to be used on FM that eliminates the need for a bias circuit? Obviously there is no relay or toggle switches to he seen.
[photo="medium"]4363[/photo] .
Some external photos of the amplifier.
[photo="medium"]4364[/photo] .
For $10, at the very least I got a heatsink and the "tin" case.
[photo="medium"]4365[/photo] .
I may be incorrect but this does not look like a commercially produced unit as I would expect to see if this was used for business band, or emergency/public services.
Like I say I have no real knowledge of amplifier design but this thing looks like it's fixed bias "class c" (FM use only) to me.
So this not truly a linear amplifier if it is biased for class c operation, I need to find an old blue Motorola book that contains sample circuits for transistors of this era..
Thank you for looking.
Best Regards
-Leap
Does anyone recognize this pcb as part of a kit?
[photo="medium"]4362[/photo] .
I think this could be used for 70 cm / Amateur TV reading the MRF646 datasheet.
[photo="medium"]4361[/photo] .
I know nothing of amplifier design but this amp can help me grasp the basics by giving me a physical layout to analyze/study. Do you see a bias circuit, because I do not, all I see are two trimmer caps on the output and two on the input, but no thermal tracking diodes; if this was to be used on FM that eliminates the need for a bias circuit? Obviously there is no relay or toggle switches to he seen.
[photo="medium"]4363[/photo] .
Some external photos of the amplifier.
[photo="medium"]4364[/photo] .
For $10, at the very least I got a heatsink and the "tin" case.
[photo="medium"]4365[/photo] .
I may be incorrect but this does not look like a commercially produced unit as I would expect to see if this was used for business band, or emergency/public services.
Like I say I have no real knowledge of amplifier design but this thing looks like it's fixed bias "class c" (FM use only) to me.
So this not truly a linear amplifier if it is biased for class c operation, I need to find an old blue Motorola book that contains sample circuits for transistors of this era..
Thank you for looking.
Best Regards
-Leap
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