Federal AM-864

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drpat said:
emrr said:
In listening, be sure to do a full polarity swap on the unit for comparison, since the side chain detection is just a single side of the PP total.

Good point, don't know how I missed that, but I'll try it.

What s meant by the full polarity swap ?


skLa1
 
hey thanks again drpat .

i was just wonder about the threshold and limiter pots, have you experience  any oscillation when both pots are turn to the max ?

skal1
 
This thing is hurting my head  drapt ,would it be possible to take some voltage reading off your unit , i do not know where you you measure from ,but i thing you have more knowledge than i  on this.

do you know what would cause this effect ?


thanks

skal1
 
hey Pat, You should drop an e-mail to walter sear at sear sound, He modded his units. IIRC he added attack and release times.  He is quite the friendly fellow and I am sure he would offer some suggestions.
 
now i am going man  :mad:  i have check the voltages and have found that their is 200 volts at pin 8 of v1 and v2 , the manual say that it should be around 155volts .


what would  cause this 50v difference The heater voltage  is not that bad it  is 7.01volts  , i should be able to use a rsistor to drop that .7volts .


skal1
 
CJ,

The only people not living in tents around here are the legislature who just rewarded their inability to pass a budget with a 20% pay raise! And yes, this place has turned into a meat market.
 
??? changed the plate resistors for 24k seems a little better , but still getting oscillation.what can cause this.

i also checked the output tx ct connection to ground i read a voltage of 1.20volts is this right , i thought should not see any dc through the secondary of the tx.


skal1
 
drapt i did change the caps in filter section , 22uf for two 12uf and 10uf for the 12uf that should be ok yes {IMP) it has not changed the hum factor.

yes this looks like an original


C2, C3 and C5 look new  markings on caps 104k


i changed the c6  for 0.01 600vac  Polypropolene Capacitors with Metal Foil ,is this ok ?

i have checked all resistors by lifting one leg from circuit and value are within  5%


skal1
 
Ok did what you suggested ,here we go


V4
pin 4 to ground ,1.4 meg 

pin 8 to R11 , 1.4 meg 


V1

pin 4 to ground ,2.67 meg 
pin 7 to C2 ,27.4 meg 
pin 8 to R2 ,12K

V2

pin 4 to ground ,2.67 meg 
pin 7 to R1 ,1.4 meg 
pin 8 to C5 ,0 OHM



skal1

 
 
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