Harrison 790 PRO racking (Photos added!)
- Thread starter ForthMonkey
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Did you have to cut the pcb?
I'm not familiar with the 790, but the pinouts look similar to my PP1, (32c-ish film mixing desk)
That aux out is probably an easy place to tap... Without the schematic it's hard to know if it will be a good line driver. if I know Harrison, it's is a 5532... You are good to go, might want to increase capacitance... Get the proper resistor etc.
The patch feed out looks like it's already balanced... Probably get good use out of that.
People often grab a signal right before the pan pot as well.
I would try all if these options, really dig Into the schematic, technically you could have more than one output, you might want to actually have an auxilarry (second output... Or third
1) transformer Balance and add an attenuator from the signal before pan pot...
2 use the aux for an unbalanced signal.
3 use the balanced patch out when you want the least components in the signal path.
I'm not familiar with the 790, but the pinouts look similar to my PP1, (32c-ish film mixing desk)
That aux out is probably an easy place to tap... Without the schematic it's hard to know if it will be a good line driver. if I know Harrison, it's is a 5532... You are good to go, might want to increase capacitance... Get the proper resistor etc.
The patch feed out looks like it's already balanced... Probably get good use out of that.
People often grab a signal right before the pan pot as well.
I would try all if these options, really dig Into the schematic, technically you could have more than one output, you might want to actually have an auxilarry (second output... Or third
1) transformer Balance and add an attenuator from the signal before pan pot...
2 use the aux for an unbalanced signal.
3 use the balanced patch out when you want the least components in the signal path.
ForthMonkey
Well-known member
Johnblue said:Did you have to cut the pcb?
I'm not familiar with the 790, but the pinouts look similar to my PP1, (32c-ish film mixing desk)
That aux out is probably an easy place to tap... Without the schematic it's hard to know if it will be a good line driver. if I know Harrison, it's is a 5532... You are good to go, might want to increase capacitance... Get the proper resistor etc.
The patch feed out looks like it's already balanced... Probably get good use out of that.
People often grab a signal right before the pan pot as well.
I would try all if these options, really dig Into the schematic, technically you could have more than one output, you might want to actually have an auxilarry (second output... Or third
1) transformer Balance and add an attenuator from the signal before pan pot...
2 use the aux for an unbalanced signal.
3 use the balanced patch out when you want the least components in the signal path.
Didn't cut PCB.I got like this.
http://i.hizliresim.com/jBGZNJ.jpg
And i got output from APL L SUM.Can't get any signal from AUX pins.
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- Sep 17, 2015
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You might have to jumper the patch send to the patch return, or wire the jacks for those tied together in a switched jack to move the signal along properly. Most patch bays would be normaled that way, interupting the signal only if a wire is inserted. Try a simple jumperwires if you aren't going to use the patch feeds.
ForthMonkey
Well-known member
Johnblue said:
Can i get signal directly from PATCH FD HI and PATCH FD LO as balanced?
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Yes, that is how it works on my desk and yours. all of the "official" ins and outs are balanced and Hi-lo is how Harrison describes that. Anywhere you see Hi-lo is a balanced connection. Those connections would basically route directly to an internal patch bay or edac connectors etc...
Any connection not marked Hi-lo is unbalanced and would route the signal to another section of the mixer.
You might have to find and jumper where where the signal leaves the PCB to the fader and returns as well.
That's probably why you aren't getting anything on the aux, your signal probably stops at the fader connection. There is probably a molex connector somewhere to attach a fader, jumper the appropriate pins there.
PFL means pre-fade listen, so you should get a signal from there regardless if you have jumpered the fader. (Obviously the connection you found as well)
I'll look for a schematic of your channel, or maybe if you have it PM me and I'll have a look.
I think a main decision you should make is if you want to have send and return, if you don't want send and return, that's the best place to easily get a balanced signal. (Wether it's before or after the fader, I don't know)
Having send and return is always awesome, and it's already all there, and it's rare that those connections are balanced, so I would take the time to figure that out.
For now, maybe jumper the send to the return, jumper the fader out to the fader in and listen to the input of the pan pot. Then you could add add an attenuator pot instead of the pan pot, as a "foux fader" for your output. With a little finesse, you could have every potential connection available.
Any connection not marked Hi-lo is unbalanced and would route the signal to another section of the mixer.
You might have to find and jumper where where the signal leaves the PCB to the fader and returns as well.
That's probably why you aren't getting anything on the aux, your signal probably stops at the fader connection. There is probably a molex connector somewhere to attach a fader, jumper the appropriate pins there.
PFL means pre-fade listen, so you should get a signal from there regardless if you have jumpered the fader. (Obviously the connection you found as well)
I'll look for a schematic of your channel, or maybe if you have it PM me and I'll have a look.
I think a main decision you should make is if you want to have send and return, if you don't want send and return, that's the best place to easily get a balanced signal. (Wether it's before or after the fader, I don't know)
Having send and return is always awesome, and it's already all there, and it's rare that those connections are balanced, so I would take the time to figure that out.
For now, maybe jumper the send to the return, jumper the fader out to the fader in and listen to the input of the pan pot. Then you could add add an attenuator pot instead of the pan pot, as a "foux fader" for your output. With a little finesse, you could have every potential connection available.
ForthMonkey
Well-known member
Thanks for explanation.
I will try Patch pins.Don't need send-return.Getting balanced output is enough for me.
If i can't get balanced out from this gear,i will try to make it balanced with transformers.
I will try Patch pins.Don't need send-return.Getting balanced output is enough for me.
If i can't get balanced out from this gear,i will try to make it balanced with transformers.
ForthMonkey
Well-known member
synthiaks said:
Yes.
I can't get balanced signal from any output but i made it balanced with trafos.Now working great.
I will share photos soon.Waiting case.
ForthMonkey
Well-known member
Added photos to first post!
Now waiting for PSU boards.Added output transformers.
Now waiting for PSU boards.Added output transformers.
- Joined
- Sep 17, 2015
- Messages
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Nice work man! You are going to love the EQs!
Some of the best in the biz. Enjoy!
Some of the best in the biz. Enjoy!
ForthMonkey
Well-known member
Johnblue said:
Thanks!
I tried units before racking and really great mic pre and eq!I believe with Lundahl transformers,it will be awesome!
Now waiting for PSU boards.Then everything will be done.
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