Search found 2067 matches
- Tue Feb 20, 2024 2:11 pm
- Forum: JLM Audio Kits
- Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
- Replies: 39
- Views: 26514
Re: MAC Rack kit Build Thread from October 2023 with slow attack led
OK that looks ok. The clue will be what ac volts you are getting at pin 6 on each IDC 10 pin header on the mac link pcb when separate and when linked measured to 0v while -5dB GR is on each channel. Make sure the switch and threshold settings on both comps are the same. Ok, So just and FYI that I w...
- Tue Feb 20, 2024 11:05 am
- Forum: JLM Audio Kits
- Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
- Replies: 39
- Views: 26514
Re: MAC Rack kit Build Thread from October 2023 with slow attack led
Yes trimpot spot is correct across makeup pot. This is very seperate from the link area of the circuit. Did the link switch work before? Do you have a photo of the link pcb? Yes the link switch used to work just fine only a slight difference between the two -5db readings on the meters when engaged....
- Mon Feb 19, 2024 7:50 pm
- Forum: JLM Audio Kits
- Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
- Replies: 39
- Views: 26514
Re: MAC Rack kit Build Thread from October 2023 with slow attack led
Ok never seen this before and the trimmer if done correctly will not affect this. Check the mac link pcb has the 10 pin headers and cables the correct way around and no shorts to 0v. With link switched on unplug one ribbon cable from the link pcb at a time to see if both comps come back to -5dB wit...
- Mon Feb 19, 2024 10:58 am
- Forum: JLM Audio Kits
- Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
- Replies: 39
- Views: 26514
Re: MAC Rack kit Build Thread from October 2023 with slow attack led
Ok, I just got done adding the trimmer pot to balance the two output pots. It wound up being 98.6K and I got the outputs VAC to be equal now when you switch on the VU meter. Thanks so much. I have done the calibration again and made some slight tweaks to adjustments trimmers but now have something ...
- Mon Feb 19, 2024 10:51 am
- Forum: JLM Audio Kits
- Topic: BA BA2 BA4 BAD Dual99v Build Thread
- Replies: 376
- Views: 881787
Re: BA BA2 BA4 BAD Dual99v Build Thread
Hi folks, got a question about the 111dc circuit boards, do any of the resisters need to be fitted? I built a BA4 with jlm 14 inputs 99v opamps and 111dc output transformers. with the 48v 25 watt power supply. They are all working but I'm getting a pulsing from the power supply. The leds get dimmer...
- Mon Feb 19, 2024 10:41 am
- Forum: JLM Audio Kits
- Topic: LA500A opto comp MAY 2021 BUILD THREAD 500/51X
- Replies: 108
- Views: 186457
Re: LA500A opto comp MAY 2021 BUILD THREAD 500/51X
Hi Joe, I've just built my LA500A. Great build, great design but sadly I have a couple of issues. What's working? Both coloured LED's, meter LED, makeup gain, hardwire bypass. No smoke What's not working? Don't appear/ hear to be getting any gain reduction. no movement on the meter regardless of sw...
- Mon Feb 19, 2024 9:32 am
- Forum: JLM Audio Kits
- Topic: JLM99*MB Kit documentation
- Replies: 26
- Views: 57356
Re: JLM99*MB Kit documentation
Hi Joe. This circuit JLM99 works in a +/-16v? I sent you a email about Go Between Plus. Thanks, Luís The JLM99*MB pcb runs the JLM99v on whatever power rails you send in which used to be +/-24vdc and then makes +/-15v rails for the dc servo ic. You could just run in +/-16v power in and link over th...
- Thu Feb 08, 2024 7:50 pm
- Forum: JLM Audio Kits
- Topic: LA500A opto comp MAY 2021 BUILD THREAD 500/51X
- Replies: 108
- Views: 186457
Re: LA500A opto comp MAY 2021 BUILD THREAD 500/51X
OK email me so we can workout the pot kit or parts you need
- Wed Feb 07, 2024 4:18 pm
- Forum: JLM Audio Kits
- Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
- Replies: 39
- Views: 26514
Re: MAC Rack kit Build Thread from October 2023 with slow attack led
Yessaxmonster wrote: ↑Wed Feb 07, 2024 3:44 pmThanks Joe,
Once I get them equal should I drop the output of my daw so that I get 1.23vac on both opto outputs so I can zero out the meter when I recalibrate?
- Wed Feb 07, 2024 3:14 pm
- Forum: JLM Audio Kits
- Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
- Replies: 39
- Views: 26514
Re: MAC Rack kit Build Thread from October 2023 with slow attack led
Hi Joe, I have started to work with figuring out what exact resistor size I would need. I have not made any changes or soldered anything yet. In doing that I decided to setup my Apogee duet interface to use for the REW Signal generator because both outputs are equal on that. With that said I sent 1...
- Wed Feb 07, 2024 2:37 pm
- Forum: JLM Audio Kits
- Topic: LA500A opto comp MAY 2021 BUILD THREAD 500/51X
- Replies: 108
- Views: 186457
- Wed Feb 07, 2024 1:41 pm
- Forum: JLM Audio Kits
- Topic: FREQ500 KIT Build Thread
- Replies: 17
- Views: 39570
Re: FREQ500 KIT Build Thread
Hello Joe, I just completed my first of two Audio Path PCBs. Per the build guide, I went to test it, inserted the two jumpers, connected it to an extender...and when I powered on my rack, the two 4R7 resistors instantly fried. Any troubleshooting tips? Best to post here or send me photos of the top...
- Tue Feb 06, 2024 7:32 am
- Forum: JLM Audio Kits
- Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
- Replies: 39
- Views: 26514
Re: MAC Rack kit Build Thread from October 2023 with slow attack led
Thanks again for all you help Joe. You can add a resistor across channel B makeup pot outside pads to balance the outputs exactly. Somewhere between 240k and 330k should balance it perfectly at the minimum makeup setting. When you have it balanced adjust the interface so both MAC outputs are 1.23va...
- Mon Feb 05, 2024 9:11 pm
- Forum: JLM Audio Kits
- Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
- Replies: 39
- Views: 26514
Re: MAC Rack kit Build Thread from October 2023 with slow attack led
Check with VU/OFF/GR in off that you have identical output levels ? Y/N I have both channels of the opto receiving 1.23 VAC and the outputs of the opto are the same but they have dropped to 1.197 VAC. This is hard relay bypass so the level difference is your interface sagging slightly under the loa...
- Mon Feb 05, 2024 2:06 pm
- Forum: JLM Audio Kits
- Topic: MAC Rack kit Build Thread from October 2023 with slow attack led
- Replies: 39
- Views: 26514
Re: MAC Rack kit Build Thread from October 2023 with slow attack led
Sorry but I am still confused on the inside / outside part. Before I pull these boards out because I can’t reach the front six soldering points cause they are covered by the case lip. Can I measure from the back 6 solder pads on each pot? Are these part of the switch or the potentiometer? I have ci...