[ARC5] BC-348Q CW Oscillator Question

[John Hutchins]

Mark -
It should be 100 K B+ to ground.
Disconnect the Power Supply, B+ wire, put tape on the lug.  Pull all the 
tubes just for fun.
Looking at the schematic I read 100K to ground with pot fully CW. 
Assuming the resistor is 94-2 is 80K and the pot (110)  measures 20k.
If the reading is less then there is a bad capacitor somewhere, or an 
added resistor, or heaven's a shorted IF transformer!
   And/Or if tubes are pulled, and the reading is still < 100K  a 
phenolic tube socket may have tin whisker short to the chassis?
If the ohm meter reads more than 100K to ground there must be a high 
resistance open in the wiring.
Those are my suggestions.
Hutch

On 1/18/2016 8:12 PM, Mark K3MSB wrote:
> Robert
>
> Thank you for your comments.  I agree if measuring resistance through 
> the wiper.   However, measuring the resistance form the end of the 80K 
> resistor should give you the sum of the 80K resistor and the Volume 
> Pot.   At max volume the pot should be 0 (ideally), so the total 
> resistance should be 80K.   But, it's not and I'm still not sure why.
>
> Mark K3MSB
>
>
>
> On Sun, Jan 17, 2016 at 1:03 AM, WA5CAB--- via ARC5 
> <arc5 at mailman.qth.net <mailto:arc5 at mailman.qth.net>> wrote:
>
>     Mark,
>
>     The table calls for rotating the Volume/Sensitivity knob fully
>     CW.  The fully CW ends of the two pots are at the bottom, not the
>     top.  With the 20K pot fully CW, the wiper is at the grounded
>     end.  So the 80K resistor has no effect.
>
>     In a message dated 01/16/2016 18:57:08 PM Central Standard Time,
>     mark.k3msb at gmail.com <mailto:mark.k3msb at gmail.com> writes:
>>     My Question. Resistor 94-2 is the 80K resistor connected to the
>>     ungrounded terminal of the volume pot.  With this in the circuit,
>>     a great many of the values in the table should be much higher. 
>>     My measured values agree with all the table values.   How can
>>     that be?  The 80K resistor is in series with the volume pot!  80K
>>     Isn't insignificant in this context....   It's easy to isolate
>>     this resistor;  it's there and it measures near 80K.
>>
>>
>>     73 Mark K3MSb
>
>
>     Robert & Susan Downs - Houston
>     wa5cab dot com (Web Store)
>     MVPA 9480
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