Help with Harbinger One build

[pryde]

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.

[paulyy]

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.

[paulyy]

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?

[paulyy]

Anybody?

[pryde]

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?

[paulyy]

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

[pryde]

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?

[paulyy]

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.

[paulyy]

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.

[fixxe]

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...

[pryde]

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

[GhostofJohnToad]

Does the lamp pulse if you jumper instead of using the rate LED?

[paulyy]

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.

[pryde]

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.

[paulyy]

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.