Thank you for producing this video, I found it very helpful. I just purchased a HY3003-3. Its documentation had alot of information. But, it was sometimes unclear. Your video answered my questions and then some. I am now very happy with my new power supply.
OP...ITs good that you opening up stuff and looking inside. Be careful when touching power supplies which run of mains voltage. The input filters (comprised of caps and inductors) can and will store prolonged charge (the inductor can store in between its distributed capacitance between the turns) and the same goes for the transformer. We want you to do more videos so take care..just a free friendly advice
I was thinking the same thing. I found a bin of 50k ten-turn pots at a local surplus shop for $7 each, and got a few of them to keep around. If that value will work (and they'll fit) I may do that. Though the more I use it the easier it's getting to dial it in with the existing controls. It'd also be fun to replace all four with rotary encoders and a little microcontroller retrofit board with four PWM outputs... spin fast for coarse adjustment and slowly for fine tuning. New project!
I just got this PSU with production year of the production of this video 2013! Got it with malfunction of slave channel. Turned out a bad 2n3055. After replacing that it is OK. Schamatic can be found on the net but be aware there are a lot of version, you need to dig until you find a right one. Having the schematic this device will serve generations. It is easy to repair and rock solid. Definitely need to change the potmeters to 10 turn ones. It is not an easy job because the 10 turn pot has 22mm diameter instead of the used one 16mm. Unfortunately the display panel lower edge is an obstacle and you should machine it out a bit. Problem is that the AD converted DIP40 socket covers this place. You have to put the AD chip into a new socket, connect the new socket to the old one with wires. During the cutting some of the pins will be destroyed of the soldered DIP40 socket. These pins shuld be soldered separately from the board to the new DIP40 socket. it is not a nice solution but it could work. Other possibe project is to change the 3 relays to SSRs. The switching noise of the relays made me a hard attack sometimes. Anyway I like this old design with its 11kg weight and old LED displays.
Heh! Thanks! The PS was about $200 with free shipping from an Amazon seller. I'm using my old Sony hard-disk camcorder from 2006. Things sure have come a long way since then. Maybe Santa will bring me an upgrade. I want to try rigging up some better lighting next time too. I do have editing software... just not very good with it yet. :)
Appears to be the same/similar unit as Dr Meter. Pricing today is around $200 OTD. Toroid transformer, no fan, two color LEDs are nice features. Frame, panel, not all PCBs are glass epoxy, are just fair. Display readings of 1% are fine for a power supply. I'd imagine noise and ripple at the higher output levels will be higher than the lower levels. That's fine too.
Nice overview! How many degrees does the potentiometers have? Standard 300 deg. like on a 16mm "volume pot", or more? Also, have you measured any under-/overshoot from turning the scope on/off. That seems to be a major problem with some chinese supplies.
Old school technology. Could have been designed in the early '80s. I guess ICs have not changed to much in 30 years. Surprised at the lack of large electrolytic caps. Curious if it's still running after almost 5 years.
I've had 2 of these...neither lived passed 6 months. The last one went out in 30 days...not worth the time to repair or the shipping to send back. Stay away from them. Look on ebay for a good used HP or just build your own like I did. My built one has been running for 6 years now.
Thank you for producing this video, I found it very helpful.
I just purchased a HY3003-3. Its documentation had alot of information. But, it was sometimes unclear.
Your video answered my questions and then some.
I am now very happy with my new power supply.
Thanks! I'm glad you found it useful.
OP...ITs good that you opening up stuff and looking inside. Be careful when touching power supplies which run of mains voltage. The input filters (comprised of caps and inductors) can and will store prolonged charge (the inductor can store in between its distributed capacitance between the turns) and the same goes for the transformer. We want you to do more videos so take care..just a free friendly advice
Great vid, very informative. Saved me a lot of headaches with my similar unit seeing you work out all the quirks.
Thanks!
I was thinking the same thing. I found a bin of 50k ten-turn pots at a local surplus shop for $7 each, and got a few of them to keep around. If that value will work (and they'll fit) I may do that. Though the more I use it the easier it's getting to dial it in with the existing controls. It'd also be fun to replace all four with rotary encoders and a little microcontroller retrofit board with four PWM outputs... spin fast for coarse adjustment and slowly for fine tuning. New project!
I just got this PSU with production year of the production of this video 2013!
Got it with malfunction of slave channel. Turned out a bad 2n3055. After replacing that it is OK. Schamatic can be found on the net but be aware there are a lot of version, you need to dig until you find a right one. Having the schematic this device will serve generations. It is easy to repair and rock solid.
Definitely need to change the potmeters to 10 turn ones. It is not an easy job because the 10 turn pot has 22mm diameter instead of the used one 16mm. Unfortunately the display panel lower edge is an obstacle and you should machine it out a bit. Problem is that the AD converted DIP40 socket covers this place. You have to put the AD chip into a new socket, connect the new socket to the old one with wires. During the cutting some of the pins will be destroyed of the soldered DIP40 socket. These pins shuld be soldered separately from the board to the new DIP40 socket. it is not a nice solution but it could work.
Other possibe project is to change the 3 relays to SSRs. The switching noise of the relays made me a hard attack sometimes. Anyway I like this old design with its 11kg weight and old LED displays.
Thanks! I see you've hot-rodded yours after a catastrophic failure... that's the way to go!
Heh! Thanks! The PS was about $200 with free shipping from an Amazon seller. I'm using my old Sony hard-disk camcorder from 2006. Things sure have come a long way since then. Maybe Santa will bring me an upgrade. I want to try rigging up some better lighting next time too. I do have editing software... just not very good with it yet. :)
Appears to be the same/similar unit as Dr Meter. Pricing today is around $200 OTD. Toroid transformer, no fan, two color LEDs are nice features.
Frame, panel, not all PCBs are glass epoxy, are just fair.
Display readings of 1% are fine for a power supply. I'd imagine noise and ripple at the higher output levels will be higher than the lower levels. That's fine too.
Nice overview! How many degrees does the potentiometers have? Standard 300 deg. like on a 16mm "volume pot", or more?
Also, have you measured any under-/overshoot from turning the scope on/off. That seems to be a major problem with some chinese supplies.
Old school technology. Could have been designed in the early '80s. I guess ICs have not changed to much in 30 years. Surprised at the lack of large electrolytic caps. Curious if it's still running after almost 5 years.
I would love to see this.
I've had 2 of these...neither lived passed 6 months. The last one went out in 30 days...not worth the time to repair or the shipping to send back. Stay away from them. Look on ebay for a good used HP or just build your own like I did. My built one has been running for 6 years now.
What does the green tap do?
Hey Todd, do you have a video on this 10 turn pot mod?
very nice :)
LM723 voltage regulator...not a 7236
Dammit... I just opened mine and found it has ZERO multi-turn trimmers. All 12 of them are the cheapo single turn >:(