@Vunce - thanks!
@xrk971 - that makes sense. I initially had my lab supply current limited to 0A140 and was getting around 16V3. Both of mine draw 0A161 or so at 18V and about 0A170 at 18V5.
Update --
Finally! I had growing pains with both amps, but they are both up and running properly. Root causes: being in a rush and breaking a trace (amp #1) and cold joint / irregular soldering (amps #1 and #2).
I still need to refine my SMT soldering methods.
I am extremely pleased. I have no basis for knowing whether my lab SMPS is "good enough" for these amps. I'll try with the battery section later and/or wire up some 9Vs. I don't have any highish impedance HPs with 1/8" jacks, so I've been using some throw away earbuds for testing and then the Meze classics and Beyer Xelentos for a few songs. In brief sessions, the amp sounds great. No critical listening, just a guy loving his new amps. No bias here, of course.
Meet the twins.
@xrk971 - that makes sense. I initially had my lab supply current limited to 0A140 and was getting around 16V3. Both of mine draw 0A161 or so at 18V and about 0A170 at 18V5.
Update --
Finally! I had growing pains with both amps, but they are both up and running properly. Root causes: being in a rush and breaking a trace (amp #1) and cold joint / irregular soldering (amps #1 and #2).
I still need to refine my SMT soldering methods.
I am extremely pleased. I have no basis for knowing whether my lab SMPS is "good enough" for these amps. I'll try with the battery section later and/or wire up some 9Vs. I don't have any highish impedance HPs with 1/8" jacks, so I've been using some throw away earbuds for testing and then the Meze classics and Beyer Xelentos for a few songs. In brief sessions, the amp sounds great. No critical listening, just a guy loving his new amps. No bias here, of course.
Meet the twins.
Zman -
I got very little sleep. I'm also running off the lab SMPS, so it may not be fair. I'll let X have the first run at any subtle differences.
What I will stand behind is that it is every bit as good as the PCA to my ears and brain. I did a quick back and forth for about 2, 1/2 song listens.
I have no way of level matching etc... but either the Hakuin is more "revealing" or easier to listen to louder. I am a firm believer in my own faults as a listener and that I am very susceptible to expectation bias. Sooooo... that's a salt mine vs. a grain of salt. YMMV, batteries not included, some assembly required, void in some countries.
Once I get more rest and more listening time over a few weeks, I'd be happy to post more thoughts if I find any meaningful differences to share. I also want to listen to the "full" package with the battery management.
I didn't try to build a PCA with the LiPo mods, so the main draw to the Hakuin for me was the new battery management. Now... whether I'll be able to get the battery management system to work is a completely different subject. That'll be next week after more parts get here. LOL!
I got very little sleep. I'm also running off the lab SMPS, so it may not be fair. I'll let X have the first run at any subtle differences.
What I will stand behind is that it is every bit as good as the PCA to my ears and brain. I did a quick back and forth for about 2, 1/2 song listens.
I have no way of level matching etc... but either the Hakuin is more "revealing" or easier to listen to louder. I am a firm believer in my own faults as a listener and that I am very susceptible to expectation bias. Sooooo... that's a salt mine vs. a grain of salt. YMMV, batteries not included, some assembly required, void in some countries.
Once I get more rest and more listening time over a few weeks, I'd be happy to post more thoughts if I find any meaningful differences to share. I also want to listen to the "full" package with the battery management.
I didn't try to build a PCA with the LiPo mods, so the main draw to the Hakuin for me was the new battery management. Now... whether I'll be able to get the battery management system to work is a completely different subject. That'll be next week after more parts get here. LOL!
Well I got in about 4 hours of listening today. This amp sounds amazing. It has all of the great sound of the MOSFET PCA, but things are more refined with more resolution. Listened with my 250ohm DT880’s. Have not tried the 55ohm OB-1’s yet. From classical to jazz, and heavy metal to classic rock, pop to girl and guitar. It’s all very balanced and great sounding.
'Scuse Me While I Kiss The Sky
I had the opportunity to A/B the PCA and Hakuin for a few hours while I was waiing for the Hakuin’s battery to drain down, so I could check the “fuel gauge” circuit.
Background
As I’ve said many times on these forums, I’m no reviewer. I don’t know how to apply all the “audiophile terms”, and I find them generally meaningless when others use them. I think I have tin ears vs. golden. But… I do love music, I listen to music almost constantly throughout every day, and I know what I like. With that said, my music doesn’t need to be “audiophile quality”. I listen to a lot of recordings that many would consider crap, and the vast majority of my music comes piped from a Sonos through my ceiling speakers. However, I’ve assembled a few decent loudspeaker systems over the years, and I own some purportedly decent headphones, IEMs, amps, DACs etc. So, if you’ll trust the opinion of a self-proclaimed music lover with a terrible case of GAS (Gear Acquisition Syndrome) – read on.
Intro
Man… I wish I had these amps 40 years or so ago when I would sit with a pair of headphones trying to write down lyrics. As an older guy trying to learn to play a bit of guitar, I know I can hear nuances and riffs – particularly in recordings multitracked with the same guitar over top of itself. If I could sing even a little, I’d use them to pick a singer out of a harmony to match. They are both exceptional amps IMO
Summary / Conclusion
So how do they differ?
In a few words. The Hakuin provides a bit more effortless detail and maybe a slight change in what I perceive as localization in and around my head.
In more words. What I love about both amps, is their ease of providing the music. I never want to take off my headphones. I never get that fatigue, headaches, or even pain associated with some rigs I’ve tried. I’ve used various PCAs for 100s of hours while traveling. There is NO “shouty” behavior anywhere… anytime. With the Hakuin, I feel like I get that same delivery, but with just a shade more detail and no added fatigue or harshness. I've heard some rigs where I can hear details exceptionally well, but they make me want to tear my ears off after 20 or 30 minutes, or I get a headache. These don't do that to me.
The only other difference I think I perceive is that with the one pair of IEMs I used, it seems to move a bit more of the far left and right… well … further left and right. Almost seems like edges are “stronger” with whatever is center stage in the “center of the head” becoming no louder, but more easily discernable. It’s no more “forward” in the middle of the perceived soundstage, but the parts of the recording that are right inside the old noggin’ (like lyrics) are more easily picked clean. There’s no degradation of what’s on the edges “in the ears and just outside”, but that potentially wee bit more separation allows whatever is front and center to be very easily heard and understood.
I still want to try it with other headphones and give it more time.
My Guesses
Notes -
Both of these were built with my amateur hands. I have no idea how they measure, but I’d give it a 90%+ shot that they perform as XRK971 intended.
The PCA has the Panasonic caps and Silmic cap changes and is running at the “standard” bias. I used sequential bugs from the reel in the build, but this one did not have super carefully hand selected/matched parts.
The Hakuin is a prototype. I don’t know whether there will be further tweaks. As with the PCA, I used sequential parts from the reel for the JFETs and BJTs. I did not go to the trouble of matching to 5 significant digits. The Hakuin does use some pretty sweet parts if you’re into that sort of thing.
Source – iPhone 6 running Qobuz. Streamed vs. Downloaded. All tracks at 16/44 or higher. HP output set to one click from max.
IEMs – Beyerdynamic Xelento
I level matched the amps using a few sections of songs and white noise by ear to the best of my ability.
I sometimes listened to 10-30s of a song before swapping amps, and sometimes I listened to a few songs. Sometimes I went back and forth a few times within a song and repeated sections. Sometimes I listened to the full song, many times I did not.
--------------------
Songs and general focus areas – I just picked some random albums and a few songs I know pretty well. It’s what I wanted to listen to this morning, plus a few things I like to use when listening for certain things. Nothing specific. I don’t “critically listen”. I don’t know how. As you’ll see – I have some eclectic? tastes…
Still Crazy After All These Years – Live in Central Park
Homeward Bound - Live in Central Park
Hey Hey – Unplugged
Midnight Rider – A Decade of Hits
Guitar work
Helplessly Hoping – So Far
Woodstock – So Far
Find the Cost of Freedom – So Far
You’re All I Need to Get By – You’re All I Need
Whiskey Lullaby - A Hundred Miles or More
Can’t Find My Way Home – Blind Faith
Everything…
Angry Chair – Unplugged
Over Now - Unplugged
The Chain – Rumours
Flight of the Cosmic Hippo
After 2nd cup… Mainly Used Just Because I Still Needed Music No Notes
What Is and Should Never Be - II
Going to California – IV (Runes) Whatever you want to call it
Dragula – Dragula
Thunder Kiss ’65 – La Sexorcisto – Devil Music Vol. 1
Ænima - Ænima
46 and 2 – Ænima
Jerk Off – Opiate
Opiate – Opiate
46 and 2 – O’Keefe Music Foundation - YouTube
Last song was from YouTube vs. Qobuz
Pic of "High-Tech A/B Rig". Notice the fancy cables
I had the opportunity to A/B the PCA and Hakuin for a few hours while I was waiing for the Hakuin’s battery to drain down, so I could check the “fuel gauge” circuit.
Background
As I’ve said many times on these forums, I’m no reviewer. I don’t know how to apply all the “audiophile terms”, and I find them generally meaningless when others use them. I think I have tin ears vs. golden. But… I do love music, I listen to music almost constantly throughout every day, and I know what I like. With that said, my music doesn’t need to be “audiophile quality”. I listen to a lot of recordings that many would consider crap, and the vast majority of my music comes piped from a Sonos through my ceiling speakers. However, I’ve assembled a few decent loudspeaker systems over the years, and I own some purportedly decent headphones, IEMs, amps, DACs etc. So, if you’ll trust the opinion of a self-proclaimed music lover with a terrible case of GAS (Gear Acquisition Syndrome) – read on.
Intro
Man… I wish I had these amps 40 years or so ago when I would sit with a pair of headphones trying to write down lyrics. As an older guy trying to learn to play a bit of guitar, I know I can hear nuances and riffs – particularly in recordings multitracked with the same guitar over top of itself. If I could sing even a little, I’d use them to pick a singer out of a harmony to match. They are both exceptional amps IMO
Summary / Conclusion
So how do they differ?
In a few words. The Hakuin provides a bit more effortless detail and maybe a slight change in what I perceive as localization in and around my head.
In more words. What I love about both amps, is their ease of providing the music. I never want to take off my headphones. I never get that fatigue, headaches, or even pain associated with some rigs I’ve tried. I’ve used various PCAs for 100s of hours while traveling. There is NO “shouty” behavior anywhere… anytime. With the Hakuin, I feel like I get that same delivery, but with just a shade more detail and no added fatigue or harshness. I've heard some rigs where I can hear details exceptionally well, but they make me want to tear my ears off after 20 or 30 minutes, or I get a headache. These don't do that to me.
The only other difference I think I perceive is that with the one pair of IEMs I used, it seems to move a bit more of the far left and right… well … further left and right. Almost seems like edges are “stronger” with whatever is center stage in the “center of the head” becoming no louder, but more easily discernable. It’s no more “forward” in the middle of the perceived soundstage, but the parts of the recording that are right inside the old noggin’ (like lyrics) are more easily picked clean. There’s no degradation of what’s on the edges “in the ears and just outside”, but that potentially wee bit more separation allows whatever is front and center to be very easily heard and understood.
I still want to try it with other headphones and give it more time.
My Guesses
- If you have a PCA and love it, you’ll probably want a Hakuin.
- If you don’t have a PCA, and need a portable amp – Once they’re out… If you get your hands on one, you'll probably want to keep it.
Notes -
Both of these were built with my amateur hands. I have no idea how they measure, but I’d give it a 90%+ shot that they perform as XRK971 intended.
The PCA has the Panasonic caps and Silmic cap changes and is running at the “standard” bias. I used sequential bugs from the reel in the build, but this one did not have super carefully hand selected/matched parts.
The Hakuin is a prototype. I don’t know whether there will be further tweaks. As with the PCA, I used sequential parts from the reel for the JFETs and BJTs. I did not go to the trouble of matching to 5 significant digits. The Hakuin does use some pretty sweet parts if you’re into that sort of thing.
Source – iPhone 6 running Qobuz. Streamed vs. Downloaded. All tracks at 16/44 or higher. HP output set to one click from max.
IEMs – Beyerdynamic Xelento
I level matched the amps using a few sections of songs and white noise by ear to the best of my ability.
I sometimes listened to 10-30s of a song before swapping amps, and sometimes I listened to a few songs. Sometimes I went back and forth a few times within a song and repeated sections. Sometimes I listened to the full song, many times I did not.
--------------------
Songs and general focus areas – I just picked some random albums and a few songs I know pretty well. It’s what I wanted to listen to this morning, plus a few things I like to use when listening for certain things. Nothing specific. I don’t “critically listen”. I don’t know how. As you’ll see – I have some eclectic? tastes…
Still Crazy After All These Years – Live in Central Park
Homeward Bound - Live in Central Park
Harmony, Guitar, Crowd Noise, and Ambience
Homeless – Graceland
Sense of space, vocals – the vocal sections and individual voices
Diamonds on the Soles of Her Shoes – GracelandLSBM Vocals and Sibilance
Nobody Knows You When You’re Down and Out – Unplugged
Hey Hey – Unplugged
Guitar work, Bass
Midnight Rider – A Decade of Hits
Guitar work
Helplessly Hoping – So Far
Woodstock – So Far
Find the Cost of Freedom – So Far
Harmony and discernment of individual voices, Guitar work
Sexual Healing – Midnight Love
Bass, Vocals
What’s Going On – What’s Going OnIntro conversation, Vocals
Ain’t No Mountain High Enough – United
You’re All I Need to Get By – You’re All I Need
Vocals – Tammi’s specifically. Shrill or not in places?
Fade Into You – So Tonight that I Might See
Lyrics… ooooooh that voice.
Fade Into You – Playing Favorites
Lyrics… ooooooh her voice too.
Whiskey Lullaby - A Hundred Miles or More
Vocals... Emotion
Molly Bawn - A Hundred Miles or MoreIntro and Vocals.. Emotion
Can’t Find My Way Home – Blind Faith
Everything…
Angry Chair – Unplugged
Over Now - Unplugged
Bass, Kick Drum, Clear Lyrics, Guitars
If I Had $1,000,000 – Gordon
Sibilance, Naturalness of voices / conversation, fiddle and accordion
One Week – StuntLyrics
The Chain – Rumours
Mick’s drumming. Harmonies.
Silver Spring – The DanceStevie’s Voice… Piano
Flight of the Cosmic Hippo
Bass, but really all of it… C’Mon!
After 2nd cup… Mainly Used Just Because I Still Needed Music No Notes
What Is and Should Never Be - II
Going to California – IV (Runes) Whatever you want to call it
Dragula – Dragula
Thunder Kiss ’65 – La Sexorcisto – Devil Music Vol. 1
Ænima - Ænima
46 and 2 – Ænima
Jerk Off – Opiate
Opiate – Opiate
46 and 2 – O’Keefe Music Foundation - YouTube
Last song was from YouTube vs. Qobuz
Pic of "High-Tech A/B Rig". Notice the fancy cables
Attachments
IAIMH,
Thanks for the detailed listening impressions. That’s a lot of tracks you went through. One thing that I did not have is a film bypass cap on the output capacitor. And it did not seem to affect the detail and resolution. I have heard that sometimes it’s actually counterproductive to bypass electrolytics with a film cap for audio frequencies.
Can you comment on the turn on / turn off sound now that a solid state relay (SSR) and voltage supervisor IC and turn on delay are implemented on the Hakuin vs the PCA, which does not have this?
Thanks,
X
Thanks for the detailed listening impressions. That’s a lot of tracks you went through. One thing that I did not have is a film bypass cap on the output capacitor. And it did not seem to affect the detail and resolution. I have heard that sometimes it’s actually counterproductive to bypass electrolytics with a film cap for audio frequencies.
Can you comment on the turn on / turn off sound now that a solid state relay (SSR) and voltage supervisor IC and turn on delay are implemented on the Hakuin vs the PCA, which does not have this?
Thanks,
X
My pleasure. Like I said in the notes, I didn't listen to all the songs all the way through, but it was plenty of listening to gather some initial impressions and feel reasonably confident. I'll have someone swap them blind on me at some point in the future. I'm as susceptible to expectation bias as the next guy.
RE: turn on / turn off. My PCAs have all had a noticeable "thump" at both turn on and turn off. It's nothing I've ever worried about re: damaging my HPs or bothering me, but it's there. The Hakuin has more of a very soft "click" than a "thump" on both turn on and off. It's much more quiet. Hope that helps.
RE: turn on / turn off. My PCAs have all had a noticeable "thump" at both turn on and turn off. It's nothing I've ever worried about re: damaging my HPs or bothering me, but it's there. The Hakuin has more of a very soft "click" than a "thump" on both turn on and off. It's much more quiet. Hope that helps.
Hi IAIMH,
A soft click for turn on and off sounds like the thump issue is fixed with the SSR and voltage supervisor and delay timer.
Any news on the charging ability of the smart charger on the PSU? It should charge without the amp being turned on. But if it doesn’t, we will need to look at that. Looks like the battery level meter needs to be looked at too.
Thanks for all your help on this!
X
A soft click for turn on and off sounds like the thump issue is fixed with the SSR and voltage supervisor and delay timer.
Any news on the charging ability of the smart charger on the PSU? It should charge without the amp being turned on. But if it doesn’t, we will need to look at that. Looks like the battery level meter needs to be looked at too.
Thanks for all your help on this!
X
X-
Great to know. Thanks! As you know I'm still a bit skittish.
I have clearly done something poorly re: the battery circuit - Charging is not working as I'd assume intended and no fuel gauge. I'll first try removing and re-flowing key parts using some heat from the bottom with a proper board heater. This was my first experience with parts having pads on the bottom, and I only soldered "from the top" with the heat gun. So, it wouldn't be absurd to think I've got a bad joint.
It may be charging, but at an excessively slow rate. I set it to charge at 11:00. Value was 3V130. At 14:00, Value was 3V150. That may even be within error margins.
It's my pleasure! This is a blast, and I'm learning a ton.
Great to know. Thanks! As you know I'm still a bit skittish.
I have clearly done something poorly re: the battery circuit - Charging is not working as I'd assume intended and no fuel gauge. I'll first try removing and re-flowing key parts using some heat from the bottom with a proper board heater. This was my first experience with parts having pads on the bottom, and I only soldered "from the top" with the heat gun. So, it wouldn't be absurd to think I've got a bad joint.
It may be charging, but at an excessively slow rate. I set it to charge at 11:00. Value was 3V130. At 14:00, Value was 3V150. That may even be within error margins.
It's my pleasure! This is a blast, and I'm learning a ton.
Hi IAIMH,
Thanks for testing all the different aspects of this smart power system: DC-DC step-up, ultra-low noise LDO voltage regulator, opto-isolated SSR anti-thump and delay, automatic battery charge when plugged into 5vdc, and battery fuel gauge.
Well, we made a lot of progress as you can see from this block diagram, now color coded with what has been tested and verified to work vs what still needs more work.
Looks like we have some debugging to do on the charging circuit and the battery fuel gauge circuit. I will hopefully get a chance to build it this weekend and we can debug in parallel.
Have you tried powering the amp with just 5v input and no LiPo? I wonder what that does? Also note that charging can only work with 5v DC input (not higher voltage).
Thanks again,
X
Thanks for testing all the different aspects of this smart power system: DC-DC step-up, ultra-low noise LDO voltage regulator, opto-isolated SSR anti-thump and delay, automatic battery charge when plugged into 5vdc, and battery fuel gauge.
Well, we made a lot of progress as you can see from this block diagram, now color coded with what has been tested and verified to work vs what still needs more work.
Looks like we have some debugging to do on the charging circuit and the battery fuel gauge circuit. I will hopefully get a chance to build it this weekend and we can debug in parallel.
Have you tried powering the amp with just 5v input and no LiPo? I wonder what that does? Also note that charging can only work with 5v DC input (not higher voltage).
Thanks again,
X
Attachments
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Hi IAIMH,
Thanks for testing all the different aspects of this smart power system: DC-DC step-up, ultra-low noise LDO voltage regulator, opto-isolated SSR anti-thump and delay, automatic battery charge when plugged into 5vdc, and battery fuel gauge.
Well, we made a lot of progress as you can see from this block diagram, now color coded with what has been tested and verified to work vs what still needs more work.
My pleasure. I'm very pleased with how few SMH moments I've had
. Runs like a champ with 5V2 and no LiPo.
Hmmmmm.... I'll try 5V0 vs 5V2 just in case and to be thorough. My wall wart puts out 5V2.
Edited to add - Does the charging system care if the thermistor is in place? I did not add one yet. That section is "open". From my limited understanding, I can't see an impact, but I'm often incorrect.
Glad to see it runs at 5.2v. I don’t think the 0.2v over 5 makes a difference. Many 5v USB supplies are like that.
The missing NTC may be the problem. The smart charger monitors a 50uA current through the NTC and if temp limit exceeds settings it suspends charging. With no NTC there, I would assume this is true. Does not appear to be an optional feature as this is related to battery overcharge safety.
If you did not get an NTC connect a 10k (maybe 6k8 can work too) resistor there to see if charging starts. I have not looked at the details of the values yet as the temp window can be programmed by adding a parallel resistor to the NTC. Please look at section 4.1.
http://ww1.microchip.com/downloads/en/DeviceDoc/MCP73871-Data-Sheet-20002090E.pdf
I bet this is why it’s not charging though.
Programming the temp range is given as an example for a typical 10k NTC to use 1.5k in series and 69k in parallel for a 0C to 50C temp range. The equations are given in Eqn 6.3. If buying an NTC without a Beta coef if temp we could calibrate it by measuring R while heating in hot water to 50C and ice water at 0C.
The missing NTC may be the problem. The smart charger monitors a 50uA current through the NTC and if temp limit exceeds settings it suspends charging. With no NTC there, I would assume this is true. Does not appear to be an optional feature as this is related to battery overcharge safety.
If you did not get an NTC connect a 10k (maybe 6k8 can work too) resistor there to see if charging starts. I have not looked at the details of the values yet as the temp window can be programmed by adding a parallel resistor to the NTC. Please look at section 4.1.
http://ww1.microchip.com/downloads/en/DeviceDoc/MCP73871-Data-Sheet-20002090E.pdf
I bet this is why it’s not charging though.
Programming the temp range is given as an example for a typical 10k NTC to use 1.5k in series and 69k in parallel for a 0C to 50C temp range. The equations are given in Eqn 6.3. If buying an NTC without a Beta coef if temp we could calibrate it by measuring R while heating in hot water to 50C and ice water at 0C.
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X -
Yep! You and I are on the same page. It seems like it is definitely not optional. I had traced it back to pin 11, but I once I pulled up the spec sheet, it was all Greek to me. Still learning.
More importantly. I bodged in a 10k resistor.
Initially, I thought it wasn't working. I powered up with 5V2. Compared to previous runs, H103 or H105 (whichever one blinks) started blinking at a much more rapid rate than previously, and my PSU was "ticking" along with it. The rate was ~2Hz or so. This continued for ~30s. The circuit was drawing a very small amount of current during each click. Then, it seems some logic kicked in, and the circuit started drawing ~1A45 at 5V2. H103 or 105 then went to a solid green vs. blinking. My current assumption is solid => charging. Blinking => charging "error" or prepping to charge perhaps.
When I take a reading across the legs of (Edited) X101, I am getting 4V07 rock steady, so the battery is getting a charging voltage.
The current draw does seem to be varying based on the "baby sitter" circuit. Over a brief time, the current lowered ~1A11. After watching it over a few minutes, the current continues to decrease, so I assume this is as the battery charges. It is at 1A02 as I type.
I will closely monitor battery temperature since there is no thermistor and report back if it indicates a "full" battery and automatically stops supplying current to the circuit. That's what I am hoping for.
Progress!
Yep! You and I are on the same page. It seems like it is definitely not optional. I had traced it back to pin 11, but I once I pulled up the spec sheet, it was all Greek to me. Still learning.
More importantly. I bodged in a 10k resistor.
Initially, I thought it wasn't working. I powered up with 5V2. Compared to previous runs, H103 or H105 (whichever one blinks) started blinking at a much more rapid rate than previously, and my PSU was "ticking" along with it. The rate was ~2Hz or so. This continued for ~30s. The circuit was drawing a very small amount of current during each click. Then, it seems some logic kicked in, and the circuit started drawing ~1A45 at 5V2. H103 or 105 then went to a solid green vs. blinking. My current assumption is solid => charging. Blinking => charging "error" or prepping to charge perhaps.
When I take a reading across the legs of (Edited) X101, I am getting 4V07 rock steady, so the battery is getting a charging voltage.
The current draw does seem to be varying based on the "baby sitter" circuit. Over a brief time, the current lowered ~1A11. After watching it over a few minutes, the current continues to decrease, so I assume this is as the battery charges. It is at 1A02 as I type.
I will closely monitor battery temperature since there is no thermistor and report back if it indicates a "full" battery and automatically stops supplying current to the circuit. That's what I am hoping for.
Progress!
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