Boss CE1 king of chorus no chorus

C

cniers13

Active member
Hello! I have a Boss CE1 clone, king of chorus V2 board. I get bypass tone and preamp gain but no chorus sound. I've poked around with an audio probe around the TDA1022 chip and haven't gotten any vibrato/chorus. The chip was from small bear. D2 is omitted because of the DC/DC converter I chose. Any help would be great!
 

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That's progress. Have to get the clock sorted next. Make sure when taking the clock measurement your one probe is on ground the other probe is on the source.
@Scruffie
Any tips on debugging this clipped oscillator kind of clock?
 
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jwin615 said:
That's progress. Have to get the clock sorted next. Make sure when taking the clock measurement your one probe is on ground the other probe is on the source.
@Scruffie
Any tips on debugging this clipped oscillator kind of clock?
Click to expand...
It's just an astable multi-vibrator, full voltages are always the place to start.

The first thing I see is the TDA1022 is only getting 11V, not the 14V indicated.

Does the converter provide enough current?
 
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Scruffie said:
It's just an astable multi-vibrator, full voltages are always the place to start.

The first thing I see is the TDA1022 is only getting 11V, not the 14V indicated.

Does the converter provide enough current?
Click to expand...
I ordered a new DC/DC converter that will supply the higher current. had the 1W version and the RD (new correct one) has 2W with double the current
 
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Seems as though there's something off with the clock, an astable multivibrator circuit

Double check the transistors and cap values for that section. No PNPs and NPNs swapped or nf value caps where pf value caps should be.
 
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jwin615 said:
Seems as though there's something off with the clock, an astable multivibrator circuit

Double check the transistors and cap values for that section. No PNPs and NPNs swapped or nf value caps where pf value caps should be.
Click to expand...
I'll confirm. I even redid the c21 22 24 and 25 today in the clock circuit
 
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jwin615 said:
Seems as though there's something off with the clock, an astable multivibrator circuit

Double check the transistors and cap values for that section. No PNPs and NPNs swapped or nf value caps where pf value caps should be.
Click to expand...
Transistors and cap values all check out. Resistors too for the clock circuit. I'm starting to think maybe it has to do with the DC DC converter but I would think it should still work at least a little bit. maybe not though
 
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Scruffie said:
Need something to work with!
Click to expand...
Got some IC DC pin voltages. DC supply was 12VDC

IC1 - Tl072
1 3mV
2 3mV
3 0
4 -14.93V
5,6,7 0
8 14.93V

IC2 - tl072
1 5.6mV
2 5.6mV
3 was spiking and falling, hard to get a read
4 -14.8V
5 0
6 3.5mV
7 around 50mV fluctuating
8 14.93

IC3 TDA1022
1 -7.7V
4 -7.24V
5 -4.28V
8 -9.2V
9 -14.9V
12 -9.92V
13 -13.93V
2, 3, 6, 7, 10, 11, 14, 15, 16 were all 0

IC4 - LM1458
1 fluctuated around 24mv to 6mV
2 0
3 -30mv to 0
4 -15V
5 0
6 -0.4
7 Fluctuated
8 15V
 
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