Well I thought I had it fixed (30V negative side) powered up in an effort to adjust offset on the D1 I/V and started checking the UBiB DC voltage. I did notice right away on that rail the LED's were a bit dimmer than the other five rails. Positive 30V supply side was fine, negative had dropped to 12V, and R1 hot, again. I've removed the PCB from it's mounts and heatsinks and measured, also check the underside for any suspect joints or shorts and see none.
For the Q's measured between Base and Collector, then Base and Emitter:
Q1: .578 .058
Q2: .424 .169
Q3: .623 .599
Q4: .335 .579
Any suggestions greatly appreciated.
For the Q's measured between Base and Collector, then Base and Emitter:
Q1: .578 .058
Q2: .424 .169
Q3: .623 .599
Q4: .335 .579
Any suggestions greatly appreciated.
Hi All,
New DIYer and need some help. I'm trying to build a UBib with 12VDC output and 300mA output current. I did quasimodo testing of my transformer Hammond 1182M15 and my Cx =0.01uF , Cs=.15uF and Rs = 16.9Ohms. I'm using https://www.mouser.com/ProductDetail/279-H4P16R9DZA as my Rs. When for R1 I'm using 2Ohms 5Watt 5% resistor.
When I turned on the power there was a loud spark. Looking closely at the board i see some blackening between Rs and Rf. Maybe one of the resistors snapped? How should i proceed to debug? Here are somepic of the project
New DIYer and need some help. I'm trying to build a UBib with 12VDC output and 300mA output current. I did quasimodo testing of my transformer Hammond 1182M15 and my Cx =0.01uF , Cs=.15uF and Rs = 16.9Ohms. I'm using https://www.mouser.com/ProductDetail/279-H4P16R9DZA as my Rs. When for R1 I'm using 2Ohms 5Watt 5% resistor.
When I turned on the power there was a loud spark. Looking closely at the board i see some blackening between Rs and Rf. Maybe one of the resistors snapped? How should i proceed to debug? Here are somepic of the project
Hi, measure the rectification diodes using the DMM's diode check mode. For a start because those sit between Rs and Rf.
Your R1 2 Ω is good for 0.29-0.3A CCS setting, if the load is 0.3A leaves no spare current in the reg for proper function.
Check that M1 M2 Mosfet types have not been mixed for position. Clean board flux, redo any joints looking not shiny/dry.
Tiny sinks for a Ubib you put, they will be unusable hot when it will be fixed, especially for 0.3A work.
Your R1 2 Ω is good for 0.29-0.3A CCS setting, if the load is 0.3A leaves no spare current in the reg for proper function.
Check that M1 M2 Mosfet types have not been mixed for position. Clean board flux, redo any joints looking not shiny/dry.
Tiny sinks for a Ubib you put, they will be unusable hot when it will be fixed, especially for 0.3A work.
Hello, so I checked, M2 and one of the leds are screwed. On the other hand I only watched Q2 and it's ok but is it better that I check the others?
Replaced Q1 and Q2. Switched R1 on both rails to 5.7R 3W since the D1 load is 18mA per rail.
Tested without the D1 dc load, the UBiB running at 30v.
Next, I will thoroughly QA the D1 before connecting Vreg dc, then adjust offset at inputs.
Salut, coach Salas!
Largish common sink, needs to drill and tap, something relatively cheap like this: 120mm Amazon heatsink
Use insulation pads and nylon grommets for the Mosfets.
Use insulation pads and nylon grommets for the Mosfets.
Without the manufacturer specifying the Rth of the heatsink, it's always a lottery. When I get back from the gym I'll take some pictures, ...the UltraBib boards have finally arrived, the gammaluminum heatsink and the mouser parts are waiting for me.
I even found an OnSemi FQP in my drawer, so I can get to building 😄
I even found an OnSemi FQP in my drawer, so I can get to building 😄
I want to buy LEDs to replace the one that no longer works but I don't know which model to choose. what should I pay attention to when choosing ?
As only one of the two LEDs is not working, do I have to change both to have the same characteristics?