Barracuda circuit ..... update (1)

[Chris]

Hi

Here is the first update. If you find some additional errors let me know. In a few days I'll post the final one if there are no more errors.

Chris

[Bill]

Re: Barracuda circuit ..... update (1)

I think you will find that Q3 & Q4 need to be matched.

And C13 & C15 need to be within +/- 1% of each other.

It would help.

Bill

[Pawel]

Re: Barracuda circuit ..... update (1)

Chris,

I haven't checked any RC in the timing circuit - so do it, please. R30 and R32 values are nonsense.

Regards,

Pawel

[Eric Foster]

Re: Barracuda circuit ..... update (1)

Also R30 looks much too high. Should be 150 ohms? There are a few other things that don't look right, but it may just be due to differences in design philosophy.

Eric.

[Bill]

I show it,

In one schematic as 120 ohm, and on different one 170 ohm.

Bill

[Bill]

Schematic before it was a Barracuda.




Here is a copy of the Barracuda before it was the Barracuda.

Originaly it was Search Scan. They have since gone out of busness. Anchor purchased the busness and did a little re-design, presto, the Barracuda.

Bill

[Chris]

Re: Schematic before it was a Barracuda.

Hi

Does someone know the value of the Z-Diodes in the SEARCH SCAN? I can't read this. The diagram is to blur at this area.

I'll post on Thursday another update of the Barracuda. So, have a look and post your error list (if there are some more).

Chris

[Bill]

Diodes & coil info.

D1, D2,& D3 = 1N4148

D5 = 1N755

D6 = 1N4001

D7 = 1N5819


( Coil )

24 turns of #26 wire on 7.5" form

[Eric Foster]

Re: Barracuda circuit ..... NE5534

The supply decoupling resistors R3 and R5 can't be right. The 5534 draws about 4mA from the supply rails and you would lose 4V across each of the 1k resistors. The current would obviously drop at the lower voltage but I measured plus/minus 1.5V supply, which is not enough. 47 ohms is about the max you want here, with larger capacitors.

22p compensation is not necessary as it slugs the bandwidth too much. The 5534 is quite stable without anything here at the gains used.

Eric.

[simeon webber]

Re: Schematic before it was a Barracuda.

d7 psu beside pump 1n 5019 is the zener i beleve it is 9.1v zener chris

d5 sounder end 1N755, GODAR, 7.5 V,zener 20 mA

the coils i think bill has it spot on .....