Gday All,
Could somebody help me out with this one please?
Finished populating my Harbinger yesterday but im having a few problems with it >:( -
I can get a bypass signal through fine and signal passes when the effect is on but there is no modulation. Lamp is always on and rate LED does not light at all. Tried jumpering the LED to see if that helped with the lamp pulse but makes no difference.
Only the volume control works, Intensity and Speed do not. Both Mod/Vin and C/V switches have signal when in both positions. Mod setting seems to get the signal to boost a fair bit so I guess that's working fine?
I have double checked all wiring, soldering, resistor values, cap values, electrolytic orientation, transistor orientation, ic's, etc and everything seems fine to me.
Gain and Offset trimmers adjust the lap intensity just fine so I cant see a problem there, I have even checked if the LDR's are working on a breadboard beforehand and they were working in both light and dark conditions, I also checked them with a torch while passing a signal to see if any modulation occurs and there is nada.
Got the DMM out and have the following voltages -
LT1054 pins
1 - 1.10v
2 - 4.99v
3 - 0.00v
4 - 0.01v
5 - 017v
6 - 2.55v
7 - 1.38v
8 - 9.58v
LM7815 Pins (viewed L - R, pins at bottom)
Left - 18.14v
Middle - 0.00v
Right - 14.86v
Any other voltages I need to check?
Im running a 1spot 9v without the filtering to power it, filtering or no filtering its the same problem. Nothing has been substituted at all, its straight a vanilla build.
Any Help is hugely appreciate!
Thanks, Mick.
Are you saying the lamp will adjust fine with the gain and offset trimmers?
Also, the "pulsing" LED does not work at all correct? Is the cathode/anode switched incorrectly?
I can post some voltages from my build for a start. I will report back.
The lamp intensity adjusts from dark to bright just fine but the lamp does not pulse, it stays on permanently, the led does not light at all, checked the polarity of the led and that was fine.
Thanks very much, that would be great!
OK I checked voltages and they are all similar with the exception of pin 5 on the LT1054. Are you sure it wasn't 0.17v? You listed 17v above.
How about orientation of D4,D5, Q11,Q12, and Q13? Maybe post some voltages of these as well. Also, detailed pics always help.
Sorry my bad, that should be 0.17v not 017v :)
I'll get the voltages of those components ASAP and post them up.
Thanks!
Ok. D4,D5, Q11, Q12 and Q13 are all orientated correctly, voltages are:
D4 - 13.53v both sides
D5 - 13.56v both sides
Q11 - E 13.89v, B 10.38v, C 14.84v
Q12 - E 13.92v, B 13.94v, C 14.84v
Q13 - E 7.48v, B 8.06v, C 8.16v
Will get some pics up soon as I can.
Try to get some pics up. Your voltages are much higher than mine here:
D4 7.8 both sides
D5 8.1 both sides
Q11- E 8.6v, B 2.7v, C 15v
Q12- E 7.2v, B 7.6v, C 15v
Q13- E 3.7v, B 4.4v, C 13v
Gonna hit the hey tonight but get some good detailed pics up and we can go from there.
No problemmo. Here are the pics of the top and bottom of the board. I hope I haven't missed something obvious and stupid :P
(http://img13.imageshack.us/img13/2723/img1567up.jpg) (http://imageshack.us/photo/my-images/13/img1567up.jpg/)
(http://img443.imageshack.us/img443/2672/img1568o.jpg) (http://imageshack.us/photo/my-images/443/img1568o.jpg/)
Nice to see Pryde trying to help you out, he built two great harbingers so if anybody can get you sorted I am sure he will.
I think you are doing the same build as myself...and notice you have not got C22 and D1 in the board, hope I am wrong on that.
I have just got mine going this morning, so I am actually about to set up the lamp.
Hope you get it up and running soon :)
I'm appreciative of any help, Pryde seems to know what he's talking about and has been happy to help so I'm very thankful for that :)
You doing the 18v or the 9v build?
I decided in the end to do the 9v as I had all the components and I use a regulated 9v supply.
I checked values from your pic to my build and everything seams to match up there.
We know that you have higher voltages on the diodes and transistors in the lamp section. This may be why your not getting the correct lamp pulsing (more qualified folks here can confirm that).
Your voltages are correct on the collectors of Q11,12,13 (~15v) but all others are high compared with mine. Since you have them socketed, can you swap in some new 5088's?
What diodes did you use for D4/D5? do you have any other 1n914's to try?
Is the dual pot wired correct? check that over again.
Is the gain trimmer for sure a 500R and not 500k?
disclaimer: My troubleshooting approach is based only on comparison with my build which works great. I don't want to send you on a wild goose chase but i think the above is worth a shot :)
I'm back on shift again so I will replace all the 2n5088's when I get time tomorrow hopefully.
Speed pot should be fine but I'll recheck just in case, I have 1n914's for the diodes as per the instructions but I'll replace those too just in case.
Thanks very much for your help Pryde! If this gets working I owe you a beer :D
Ensure that gain trimmer is 500R as well.
Sorry for the late reply Pryde!
Changed all the 5088's, double checked the trim pot and its a 500r, replaced the diodes with new ones and still getting the same issues.
I don't know what else to do man. I might reflow all the solder joints and see if that helps, if not im outta ideas :(
Thats a good plan. Never hurts to re-flow. And really check close for solder bridges as well. Just be patient, we will get it sorted. There are ALOT of very skilled troubleshooters here, including the Bean himself so be at ease
I keep wondering about Q13 as the collector voltage is very low (should be ~14v). triple check component values R46, R47, R52, R53 and reflow everything around Q13 as well
Post some new voltages after this as well.
New to this forum. I seem to be having the same issues as Mycpotter . Everything is working except the lamp. The led is pulsing when the seed knob is turned up but not the lamp. The lamp is on and can be adjusted with the trimmers but just doesn't pulse on its own. I notice I'm the only one so far to use the 18V power supply with this project. I'm using th Dunlop ECB004US AC adapter. I'll try and post more when I get more time.
Ok. I got it to work after hours of debugging. No matter what I would do/change. Nothing worked so I took the lamp out and used it like a probe. I know by doing this, I run risk of burning the lamp but I was at my wits end. I just wanted the dame thing to work. I soldered two wires to each lug of the lamp. I hooked one side up to where the lamp would go. The eyelet that goes to Q13 "C". The other wire ended up going in between R45 and Q12 "E" and it worked but this doesn't match up with the schematic. Will this be ok to do? The voltage readings looked good. I even check other univibe schematic to confirm. Any thoughts?
Anybody? ???
Hello Paulyy
I am really not sure why or how you are getting the circuit to work with your findings. I think MB will need to weigh-in here. You are bypassing the collector of Q11 and Q12 altogether where the lamp taps 15v. Are you still getting 15v at that area of the lamp?
15 on both Q11 and Q12. Both the base B and E seem to around 7 to 9 volts. The muiltemeter keeps moving. I don't get it
Just so we are clear, you have one lead of the lamp on the pad that joins with R53/Q13...
and the other lead is connected to R45/Q12 emitter?
This works and you are getting lamp pulsing?
When you hook the lamp up normally, you are not getting lamp pulsing?
Exactly. When I hook it up like it should be, The light comes on but no pulsing. I can adjust the trimmers and the light will respond to me moving the trimmers but wont pulse. When do it the other way it works.
I'm thinking it might have something to do with R46 and Q13. I've tried 4.7 for R46 and a MPSA18 for Q13 but seem to get the same results. I'll keep trying.
Ok, I have the same problem: Rate Led does not light and light bulb just stays on.
Now on accident I found out that when I let the rate-led's legs touch, the bulb works. So maybe you want to try that :)
To the others: How do I fix this problem? Does that just mean that my Led is dead?
Sorry, not trying to derail the thread...
Not sure but it may be possible there is something up with the pcb itself as atleast 3 people have "seamingly" the same issue happening. I don't know as both my builds went off fine. Maybe Bean can shed some light
Does the lamp pulse if you jumper instead of using the rate LED?
My rate LED works but the bulb just stays on. I tried jumping the LED but nothing happens. When I move the one leg of the lamp that's suppose to go to the C of Q11/Q12 and move it to E of Q11/Q12, Both the LED and bulb work. Here's some Volt readings
Q11 C 14.9
B 6.8/7.5
E 7.7/9.1
Q12 C 15.0
B 7.6/9.1
E 7.0/8.5
Q13 C 9.5
B 1.2
E 0.5
Hope those readings help and thanks for the help.
Q13 voltages are very low compared to mine. Here again are my reference voltages:
D4 7.8 both sides
D5 8.1 both sides
Q11- E 8.6v, B 2.7v, C 15v
Q12- E 7.2v, B 7.6v, C 15v
Q13- E 3.7v, B 4.4v, C 13v
I'm sure you have checked all components but do so again, one more time never hurts.
Thank you pryde for the help. I'll check it tonight and see what I could find. Are you using the bulb that Bean recommends. The 7371. I have five of them and they all do the same thing.
;D It WORKS!!!!!!!!!!!
The 50K INT pot was wired wrong. I had lug one and two mixed up. Rookie move. I should say that I haven't plug it in to my amp yet but the lamp is pulsing and so is the led. I need to get to bed but thank you everyone for helping. I'll be posting more info if something else goes wrong.
Good to hear! :)
*diode-destroyer-high-five*
Thanks Fixxe. Now its time for mods. ;D
Finally got back to working in this after a much needed holiday:
Harbinger is now working perfectly, as it turns out R45 which I believe connects to the rate LED wasn't getting to ground so the LFO wasn't able to start without it, for some reason jumpering the rate LED pads or having an LED installed didn't make the required connection (i may have broken a trace somehow...) so I ran a wire from the pads direct to ground and presto, swirly goodness for some reason :)
Thanks very much to Pryde for his patience and help!!!
Hi,
This is the first pedal I have built for a few years but I have been building EQ's, pre-amps and the odd compressor in the meantime all of which work nicely. That's the good bit. I have got the Harbinger all nicely constructed and it does seem to do what it's supposed to do ie. speed, intensity, gain etc work. Fet position for more gain works, but I must admit, the sound coming out is far from lush! I am getting quite a good bird impersonation (like a tweet!!) coming through with no input signal and the sound in general is very harsh like diode clipping. I have checked all of the component values and orientations and they are OK. The only change from the original is that I used a 200K trimmer for the offset as I couldn't get a 250K one. I couldn't see this making much difference as hopefully the trimmers would end up around middle sort of values. The lamp intensity seems to be just fine so I can't imagine it's far off being right but clearly it isn't. I can't find any solder bridges nor have I spotted any dry joints. Incidentally I am using the 9v layout and a 9v dc regulated supply. Has anyone had this sort of problem before?
Any advice is much appreciated.
Cheers
Steve
I can answer my own submission! I think there were a number of small issues which made things messy. The power supply wasn't regulated so I've fitted the filter board after which the performance was almost non existent. However when I checked the voltages I found I was getting around 5.6V dc before I remembered the issue with R54. I jumpered this and lo and behold it's all working nicely. Thanks for a great site!
Cheers
Steve