Highway 89 voltages???

[Barcode80]

I am getting no signal from my newly built highway 89. i figure it is a wiring problem, as a bias problem as i understand usually results in crap sound but usually at least a faint signal. however, can someone post your voltages from a working build for comparison?

[Barcode80]

okay, so i changed out a pot (i had salvaged one) and now i get faint, muffled, and gated signal. which i assume means a misbiased tranny and therefore most likely a solder bridge. however, i've gone over the whole vero and recut the traces and separated them with an exacto, and i also remelted every join on the board. no dice. thoughts?

[petemoore]

  Jfets bias funny, see GEO for info.
  Bias the Jfets.
  Use audio probe.
 

[Barcode80]

um, no fets in this circuit, it calls for 5089's

[John Lyons]

I'll try to get you the voltages tomorrow. I had mine apart to put in a box. Stay tuned.

John

[John Lyons]

Sorry about the delay. Here are my hwy 89 voltages:

Q1
C 3.8 - 4.1v (depending on gain pot setting) 
B 1.7v 
E 1v

Q2
C 9.6 (9.6 volt supply)
B 1.5v
E 1v

Q3
C 4.6v 
B 1v
E .5 v

Hope this helps you.

John

[Barcode80]

ok, yeah, my voltages are nowhere near those. i don't remember them exactly right now (i'm at work) but i'll check and post them later today.

[Barcode80]

okay, here are my voltages, assuming that ulysses' layout (in his gallery, which i used) is marked the same as the schem:

Q1:
5.65
.69
.14

Q2:
8.5
.85
.4

Q3:
8.83
.4
0

see? WAY off. on all three even 

[petemoore]

  Daft, I started typing and don't want to, I don't know for sure if there's a buffer in there, But suspect these voltages offered as reference by Basicaudio are from a working circuit:
  Q1
C 3.8 - 4.1v (depending on gain pot setting) 
B 1.7v 
E 1v
  And your voltages look to be within operational range for a gain stage here, I would audio probe B/C of Q1 or look at Q2...
Q2
C 9.6 (9.6 volt supply)
B 1.5v
E 1v
  which must be a buffer stage, as no signal would be heard if the collector [@ supply voltage] were the assigned as output, the emitter @ 1v though would look to me now as not having much room to swing toward ground, perhaps that's part of the circuit 'gig'.
Q3
C 4.6v 
B 1v
E .5 v
  This one looks like a gain stage, collector around 1/2v, base above emitter, emitter having a small resistor, lifting it .5v from ground.
------
Q1:
5.65
.69
.14

Q2:
8.5 I assume your battery is 8.83v?
.85
.4 I would measure the emitter resistor on this one.

Q3:
8.83 For some reason this one looks near or at supply..are they connected?
.4
0  And this one shows no V where BA's voltages show .5v
  I would measure across every resistor [around the Q's with suspicious voltage readings] from most distant points, through as many solder connections as possible..

[96ecss]

okay, here are my voltages, assuming that ulysses' layout (in his gallery, which i used) is marked the same as the schem:

Q1:
5.65
.69
.14

Q2:
8.5
.85
.4

Q3:
8.83
.4
0

see? WAY off. on all three even 

Barcode80, did you ever get this fixed? I'm having the same exact problem with mine. Voltages are almost identical and output is the same as yours. The last place in my circuit that has strong sound with my audio probe is the Base of Q3. I resoldered it and then I replaced it with no change in results.

Dave

[clsnacky]

Reverse the orientation of all the transistors, that worked for me. 

[96ecss]

Reverse the orientation of all the transistors, that worked for me. 

I actually was just going to post that. I took a look at the schem and saw that the orientation was wrong. I switched them and the problem is solved. Thanks anyway for your help.

Dave

[Barcode80]

SWEET i'll try that when i get home. glad i didn't tear it apart

[96ecss]

It's really a great sounding pedal. I just played a bunch of Gov't Mule songs with it and it definitely sounds great for Hard Rock. I played my 71 Gibson SG with Seymour Duncan JB in the bridge through just the Hwy 89 and my Fender Blues Duluxe amp. I'll give it a try later tonight with my 335. I'll be boxing it up tonight too.

Dave

[ulysses]

this is prob my fault.. did you build my vero version of the hwy 89?

i dont know what brand they where, but i had some 5089's that appear to be a different orientation to the fairchild ones that everyone is using.

i am about to update my vero layout with the trannies turned around and the schem attached..

damn, i wonder how many people put this one in the bin without checking the trannie orientation on the schem..

i am also now starting to put the pin letters (CBE etc) on my new layouts so its easier for people to check the orientation of THEIR trannies.

cheers
ulysses

[96ecss]

Hi Ulysses,

Yes I used your vero layout. When it didn't work, I got out my DMM and audio probe and started troubleshooting. When I got stumped I took a break for an hour. When I went back to it, I looked at the schematic and it jumped right out at me. By the time I posted again, somebody beat me to the answer.

  I was going to etch my own PCB for this build but I came across your layout and I had a piece of vero left over from another build that was exactly the right size for this so I just used that instead.

I don't blame you at all for the mistake. I always check the schematic for trany orientation BEFORE I build a pedal from someone else's layout. I didn't do that this time and it bit me in the ass. I blame myself for breaking my own rule and not checking. I would like to thank you though for the vero layout. It really is a good sounding OD.

Dave

[ulysses]

glad you liked the vero layout.

it is a really nice sounding circuit. i would classify it as a distortion and not an overdrive like everyone else says it is

i tracked down those reverse orientation transistors - phillips 2n5089's - why one company makes the orientation different to everyone else is beyond me! 

the layout gallery is down atm, will post the new layout when it is back up.

cheers
ulysses

[96ecss]

I agree about it being a distortion pedal. It will do medium overdrive but I like it better with the gain all the way up and I control it with the volume knob on my guitar.

Dave

[markm]

i am also now starting to put the pin letters (CBE etc) on my new layouts so its easier for people to check the orientation of THEIR trannies.

I've started to do this too but, sometimes I forget.......
Nice work Ulysses!