sbelyo Posted December 30, 2017 Report Share Posted December 30, 2017 interested too Quote Link to comment Share on other sites More sharing options...
cspirou Posted December 30, 2017 Report Share Posted December 30, 2017 I assume the feedback resistors will be left off so we can set our own voltage? Or could we request different voltages? Quote Link to comment Share on other sites More sharing options...
luvdunhill Posted December 30, 2017 Report Share Posted December 30, 2017 I assume the feedback resistors will be left off so we can set our own voltage? Or could we request different voltages?Yeah.It would have user settable resistors, or I can add them before shipping them if you ask real nice 1 Quote Link to comment Share on other sites More sharing options...
jgazal Posted December 30, 2017 Report Share Posted December 30, 2017 Interested too. Quote Link to comment Share on other sites More sharing options...
biosonar Posted December 30, 2017 Report Share Posted December 30, 2017 I am interested in 2. Quote Link to comment Share on other sites More sharing options...
rumina Posted December 31, 2017 Report Share Posted December 31, 2017 Definitely interested. Quote Link to comment Share on other sites More sharing options...
jose Posted December 31, 2017 Report Share Posted December 31, 2017 Sorry guys. Yesterday I finished my second GRLV ready for 23,3volt but I have a problem. Rail + is ok with +23,37volt. but negative I only have -13,23volt. I have some measures: I changed Q10 because I thought that it´s wrong but with a new Ksp42 I have the same values. The Led´s shine in the same way. I do not know what is wrong. I suspect 15031 or 21193 but I'm not sure. Can you give me any recommendation? Thanks... and happy new year !!!! Quote Link to comment Share on other sites More sharing options...
sorenb Posted December 31, 2017 Report Share Posted December 31, 2017 What voltage do you have before regulation? what is the voltage at OpAmp pin3/pin2, 10V? did you check that you haven't by accident swapped a KSP42 for KSP92 ? Quote Link to comment Share on other sites More sharing options...
jose Posted December 31, 2017 Report Share Posted December 31, 2017 Before regulation I have 33 volt on both sides and 10v on pins 2 and 3. What do you think? Quote Link to comment Share on other sites More sharing options...
kevin gilmore Posted December 31, 2017 Author Report Share Posted December 31, 2017 check the values or r9 and r10, it looks like everything is working right if both input pins of the opamp are at -10v Quote Link to comment Share on other sites More sharing options...
sorenb Posted December 31, 2017 Report Share Posted December 31, 2017 check Q11 Quote Link to comment Share on other sites More sharing options...
Pars Posted December 31, 2017 Report Share Posted December 31, 2017 On 12/29/2017 at 8:27 AM, luvdunhill said: I would consider doing an assembled run of these, but we would need a decent amount of interest. I'd be interested in some as well. I presume these would have the same limitations in terms of voltage range as the normal GRLV does? Could you do 5V, etc. with these assuming the reference, etc. were changed? Quote Link to comment Share on other sites More sharing options...
kevin gilmore Posted December 31, 2017 Author Report Share Posted December 31, 2017 (edited) can't do 5V. best you can probably do is 12V and then you still have to change the reference to a 5V reference check C3 to make sure its not in backwards Edited December 31, 2017 by kevin gilmore Quote Link to comment Share on other sites More sharing options...
mwl168 Posted January 1, 2018 Report Share Posted January 1, 2018 11 hours ago, jose said: It's difficult for me to ascertain from the photo but those diode boards orientation looks suspicious to me. Double check and make sure the board for the negative rail is mounted correctly. Quote Link to comment Share on other sites More sharing options...
Pars Posted January 1, 2018 Report Share Posted January 1, 2018 I'd noticed the same thing Michael... I think the newer boards with 3 bridges have all the bridges oriented the same way. I think the older boards like we are using had them reversed. Quote Link to comment Share on other sites More sharing options...
Blueman2 Posted January 1, 2018 Report Share Posted January 1, 2018 (edited) Version .44, which I think he is using, has all 3 bridges with key at bottom. Here is bare board I have: Edited January 1, 2018 by Blueman2 Quote Link to comment Share on other sites More sharing options...
mwl168 Posted January 1, 2018 Report Share Posted January 1, 2018 (edited) Thanks guys! I know that it's unlikely the rectifier would be the problem given Jose is getting output just not the intended potential. I should have checked before I typed... Does adjusting the negative rail trim pot do anything? Edited January 1, 2018 by mwl168 Quote Link to comment Share on other sites More sharing options...
Blueman2 Posted January 1, 2018 Report Share Posted January 1, 2018 (edited) Maybe is it just a shadow, But does the left bridge capacitor look burnt?? That is the + side, so probably not the issue anyway. Edited January 1, 2018 by Blueman2 Quote Link to comment Share on other sites More sharing options...
Pars Posted January 1, 2018 Report Share Posted January 1, 2018 Looks ok, but that probably wouldn't cause an issue anyhow. Check to make sure all the bridge diodes are oriented correctly. Quote Link to comment Share on other sites More sharing options...
Kerry Posted January 1, 2018 Report Share Posted January 1, 2018 I've just been learning Eagle. They have a great integration to Fusion 360 since it was purchased by Autodesk. I've redone the GR78xx as my first test. Still learning a lot, but getting there. Here's some renderings after I pushed it to Fusion... I've still got some work to do, but this looks very promising. Most things seem to be rendering properly, though the solder mask isn't coming over and the fonts seem off a bit. Once I have my boards in Eagle, I'll be able to drop the boards into my mechanical models. I'm very excited PS My plan was to use only three pins to connect to the main PS board. Pins 1 & 5 are duplicates of 2 & 4. 9 Quote Link to comment Share on other sites More sharing options...
cspirou Posted January 1, 2018 Report Share Posted January 1, 2018 Very nice @Kerry! That pinout looks compatible with the Dynalo Mini board. Quote Link to comment Share on other sites More sharing options...
ruslanch Posted January 1, 2018 Report Share Posted January 1, 2018 I remade my previous GRLV pcb for my amplifier: 1. Optimized the pcb size. 2. Fixed bugs of the previous version - added forgotten capacitors in the supply chain for op amps, the supply of all internal circuits takes from the pure part of the circuit, as in the original version of the board. 3. Now this is the native KiCad project, not the conversion from Eagle. Gerbers, KiCad project, 3D view Quote Link to comment Share on other sites More sharing options...
jose Posted January 1, 2018 Report Share Posted January 1, 2018 Thanks boys for replies. Yes, I use the ver. 0.44 so + is in front. I have before regulation -33Vdc. Maybe I can be wrong but I think that the bridge is OK but... (By the way, Pars, thanks for the diode board) Yesterday I was checking and cleaning up some things; 1. R9 and R10 it´s ok (2k and 1.5K). Identical values on both sides 2. I changed Q2,Q10,Q13,Q11, Q5 (and D6 for try something) With the same result. -13,23volt. 3. I move trimpot (100K) but I haven´t any variation The first difference that I find between both rails is at the anode D6 (-14,9volt) and D4 (+15,64volt). 4. Volt in Pin2 and Pin3 (OPA134) is -10volt This afternoon I will concentrate on the area of Q12, 1N914 and Trimpot. Quote Link to comment Share on other sites More sharing options...
mwl168 Posted January 1, 2018 Report Share Posted January 1, 2018 @ jose: Have you tried swapping the OP's and voltage reference between the two rails to see if that makes a difference? Quote Link to comment Share on other sites More sharing options...
sorenb Posted January 1, 2018 Report Share Posted January 1, 2018 1 hour ago, jose said: Yesterday I was checking and cleaning up some things; 1. R9 and R10 it´s ok (2k and 1.5K). Identical values on both sides 2. I changed Q2,Q10,Q13,Q11, Q5 (and D6 for try something) With the same result. -13,23volt. 3. I move trimpot (100K) but I haven´t any variation The first difference that I find between both rails is at the anode D6 (-14,9volt) and D4 (+15,64volt). 4. Volt in Pin2 and Pin3 (OPA134) is -10volt This afternoon I will concentrate on the area of Q12, 1N914 and Trimpot. it's a bit "odd" that you have -3.23V across the R9 (2k) (meaning 1.6mA), and at the same time 10V across R10 (1k5) (meaning 6.7mA) , so where does the remainder 5.1mA go? C3 as Kevin points to seems to be a reasonable guess ...provided that the 1Megs resistors are correct (which it seems from your pics), or the OpAmp itself ... Quote Link to comment Share on other sites More sharing options...
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