#garfield Logs

May 21 2021

09:21 AM rue_mohr: you didn't miss anything
01:38 PM Tom_L: supposedly they've been working on the service here
04:07 PM Tom_L: rue_mohr, don't forget to call whoever it was you were to call RIGHT NOW!!!!!!!
04:08 PM Tom_L: HEAD GASKET GUY!!! DAMMIT!! DO IT!
04:08 PM polprog: aaaand i took one of the ne5534 opamps from aliexpress and it doesnt chooch like it should
04:09 PM polprog: voltage follower output 1.something instead of 8V (18 V supply)
04:09 PM polprog: ive gotta build a small inverting circuit and test all of them
04:09 PM rue_mohr: I stopped in today and got a head gasket
04:09 PM rue_mohr: thanks for suggesting I take a pic
04:10 PM rue_mohr: polprog, the 5534 is great, but needs LOTS of headroom
04:10 PM rue_mohr: like 3V
04:10 PM polprog: i was trying to use it as a voltage source for the bessel filter
04:10 PM rue_mohr: so if you have a 7V supply, you have 1V room for signal
04:10 PM polprog: i needed something in between the rails
04:10 PM polprog: there was enoug room...
04:10 PM rue_mohr: or to get that power convrter working
04:10 PM polprog: it was right in the middle of the supply voltage
04:11 PM rue_mohr: you want about 1mH primary on the coil
04:11 PM rue_mohr: in about 20 turns
04:11 PM rue_mohr: (say 17 to 30 turns)
04:18 PM Tom_L: did they say the gasket was a weak spot?
04:25 PM rue_mohr: he was surprised they had one in stock
04:25 PM rue_mohr: I wasn't
04:25 PM rue_mohr: so, whatever
04:25 PM Tom_L: heh
04:26 PM rue_mohr: if you look up those engones, they have major failures with the head gasket
04:26 PM rue_mohr: s
04:26 PM rue_mohr: mines at 24 hrs,
04:26 PM rue_mohr: some of them get 30, 50, 100
04:32 PM polprog: damn
04:32 PM polprog: blew only 3 jfets, done a bit of reading
04:32 PM polprog: and suddenly this thing is somewhat understandable
04:32 PM polprog: https://i.imgur.com/WOeu5C5.png
04:33 PM polprog: 23GHz receiver
04:33 PM rue_mohr: hah I hate RF
09:03 PM rue_bed2: I wonder if we actually generate a lot of rf noise
09:05 PM rue_bed2: http://www.talkingelectronics.com/projects/50%20-%20555%20Circuits/50%20-%20555%20Circuits.html?epik=0ELZDE_IWX2Zw
09:05 PM rue_bed2: some 555 stuff, not all usefull, some verry
09:06 PM rue_bed2: https://circuits-diy.com/dual-power-supply-using-555-timer-ic/
09:06 PM rue_bed2: cute trick
09:06 PM rue_bed2: http://www.555-timer-circuits.com/laser-ray-sound.html that too
09:07 PM rue_bed2: http://www.unitechelectronics.com/NE-555P3.htm there is a table there that shows a difference between two types of 555