Heathkit HW-101 Part #3: I Have The Power (Supply)!
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- Опубліковано 4 сер 2022
- I won't get any further with this project without a functioning power supply, so this episode is all about getting the Heathkit HP-23 power supply working again.
It needs new capacitors, resistors, and diodes, and I'll show my approach for replacing the original parts with more compact modern components.
No endorsement is made nor implied to any commercial products referenced in this episode.
Nice job many thanks for time and generosity
You might care to check the schematics for the HP-23 vs the HP-23A. When you examine those carefully, you will find that the first model, the HP-23, shows 268 VAC out of the HV winding, while the HP-23A and subsequent models show that voltage as 282 VAC. Since these are voltage-doubler supplies, that means that in the first case, the unloaded DC voltage output is 2.828 X 262 = ~ 740 VDC, whereas in the later supplies, that voltage is ~798 VDC, This is a significant difference.
You didn't consider load testing? I know you'd need a variety of loads but working that out is part of the fun!
Nice job, but I would use the old capacitor housing to store the new electronics inside it. So you will not lose the rare look of the entire device.
Thanks for this video!
Is there anywhere to download that PCB and parts list?
Did you run the input AC up to ~120+ VAC to see what the impact was on the supply voltages? 115 VAC seems a bit low for typical line voltages nowadays in the U.S. Great work can't wait to see the old girl up and running on the air! 73 - Dino KLØS
Thanks and good catch. I didn't do that check during the video, so I did it just today. At a measured 124 VAC line power input, here's the measured outputs (with no load on them): 793 VDC, 355 VDC, and -129 VDC. The HV is still a bit low (820 VDC nominal per the manual at 120 VAC input), and of course the voltage when loaded to nominal 250mA is more important. I'll check it under load before I hook it up to the HW-101.
👍
good work ... thank you for this great video ... 73s de DL6RDE / AA1KD, Charlie
Excellent. As you are continually faced with the problem of the smell of smoke, what is your plan for sealing the old choke?
The choke seems OK so far. It passes the room temp sniff test, there's no odor unlike the caps. So I am hopeful once its warmed up its gonna be OK.