Episode: 2004
Title: HPR2004: A First Look at the Owon B35T
Source: https://hub.hackerpublicradio.org/ccdn.php?filename=/eps/hpr2004/hpr2004.mp3
Transcribed: 2025-10-18 13:12:40

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This in HPR episode 2004 entitled, A First Look at the OMB 35D, it is hosted by Enable
and in about 36 minutes long.
The summer is, you are long for the ride and Enable takes its first look at another inexpensive
multimeter.
This episode of HPR is brought to you by AnanasThost.com.
Get 15% discount on all shared hosting with the offer code, HPR15, that's HPR15.
Better web hosting that's honest and fair at AnanasThost.com.
Hello, this is Anway Bill, and I'm here with another multimeter review.
I don't know if we're up to a series now with this or not, but I was just looking around
online, I forget what I was looking for, it wasn't four meter, but I'm on Amazon and
somehow this comes up and people also bought, and I had never seen this meter before.
When meters get down into the $35 range, sometimes I get a laugh and wonder what could
be coming out of China for $35 and how good could it be.
So I kind of just ordered it spur the moment, and I thought why not when I just opened
it up and play around with it, first of all, just like kind of do a little unboxing.
You're just going to have to pretend this is YouTube and you can see a box opening right
now.
So I just took a picture of it, and I'll take a few pictures as I go along, I'll put
them up in the show notes.
This is a company called O1, O-W-O-N.
I've noticed that stuff coming out of China will just get rebranded, you know, 16 different
ways, and it's all like the unity meters that I previously did a review on.
I see them under like six or seven different name brands, and sometimes they just change
the colors, sometimes they change the names, but they're all out there.
So anyways, this one is an O-W-O-N, O-W-O-N, I guess we're going to say.
And let's see, the description is O-W-O-N, B35T, multimeter with Bluetooth.
That's why I bought this, it has Bluetooth.
It just made me laugh, and so I had to get it for $35.
I see this same meter going for about $60.
That seems to be with a carry case and like extra leads and alligator clips.
I don't even know what type of leads are in here yet, but I don't think they stuffed
a case in here too.
Maybe they did.
I'm looking at a cardboard box at the moment, but I saw this for $35, you know, it wasn't
the $60 price range, I saw it for $47.
I got to $35, I just pulled the trigger on it.
When I researched it a bit before I bought it, there is a B35 out there.
That is an analog, or not an analog, that's a digital auto-ranging meter.
And what I recommend you get and what I've recommended in the past is a true RMS meter,
which will read AC voltage, the sine wave, and give you a proper reading with, you know,
root mean square, not, you know, peak to peak or not average as it goes along the
sine.
It's actually doing the math and telling you how much power that sine wave is giving
you.
So the T is what you want, B35T.
That is the true RMS.
So, okay, let me open this beast up.
Oh, they did give a little case.
There is a little black case.
I'll have to take a picture of that to a little black carry case.
Oh, another thing this had, which I found lacking in the unity, which I don't think this
is going to replace the new T.
I can already tell by looking at the specs that, let's see, let's over here, unity, I always
forget the model number of this thing, unity UT61E.
If you look in HPR back in some of my shows, I did a review of this meter, and this is
the meter I like to carry and use for electronics use.
The Oon, I just got such a kick out of this Bluetooth thing, I just got to see it.
Just download an app and it's going to send the meter's readings and logging up to
my Android phone.
I can't believe for 35 bucks they can do this.
All right, let me open this thing up, okay, it's blue.
If you hear, oh, it's lighter than I thought it would be.
Maybe the batteries aren't it yet.
Yeah, I don't think there's a battery in it yet.
Let me get a screwdriver, you're just along for the ride now.
Which one of you can tell me where my screwdrivers are?
They were on the computer desk, not where they should be.
It takes two double A's, which they did not provide, so let me go get some batteries as
well.
If you can hear any wildlife sounds, it's because I finally have the windows open, and
the computer or the electronics bench is right under a window, finally feels like spring.
This is conversation.
This is battery insertion, battery insertion filibuster in there.
All right, the battery's in, before I turn it on, I'll just see what else we got here.
Leads, those give you leads.
I see a multifunction socket, I'm not sure if that leads, so leads feel better than the
Unity, soft cable.
Unity ones just kind of stay bunched up.
They have end protectors on their tight, they have the end caps, I'll just take a picture
of this too.
They have the end caps and then they have the retention screw on the probe itself so you
can screw in accessories instead of just sliding them on and you get an imprecise connection,
that's an alligator clip.
These ones screw on, you're sure you got a nice tight connection, see if I can zoom
in on that.
It's got a temperature probe, oh that must go, oh no, oh it's one of those, okay, I don't
know, which type of temperature probe, but I suppose I could play with that too, now
we need a knife, I should prepare this better and have this stuff laid out, oh you do get
alligator clips with it, so these must be the screw on pipe.
Well as inexpensive meters go, the probes and these screw on accessories, they're beating
the unity, not that this is a, oh wait, yeah, screw on alligator clips with a nice tight
threaded retention.
This isn't a challenge between unity and oh on here, I'm just, if you listen to my previous
review, I might have bashed the probes a bit, I don't even use the unity probes, I bought
a set of x-tap probes that I like better, okay, this little multifunction tool is very similar
to the, again, if you heard my unity review, it comes with this little doohickey that
you can insert into the, I'm not sure where because this doesn't really line up, insert
into the meter and then you can put in like resistors, capacitors through whole leads
to see what the capacitance is, this one will also do NPN, PNP, transistors, but it does
not have the pads like the unity did where you can play surface mount components on there
with a pair of tweezers that, if you twist your tweezers, the part goes flying and it's
lost into the nap of the rug and you will never get it back, I'm speaking from experience
there.
Okay, that's all the parts, let me see, so there it says, oh on B35T, true RMS, digital
multimeter, volt, let's see, I'm going to turn it off for the first time, see if we get
a beep, no beep, defaults to DC, I like that for electronics, let me see how you change
it, range, select, select, yep, press select, you can go AC, DC, that's good, I like, then
you go to milli volts, default to DC again, select as AC, next range is diode checking,
looks like capacitance, resistance and continuity, yep, you can just cycle through those with
select, next function is hertz, next function is F, H, F, E, look at that, V, frequency,
I'm going to look in the book, let's see if the book is in English, H, F, E is transistor
measurement, okay, so it has its own selector for, its own spot on the rotary switch for
transistors, interesting, next one is temperature, I forget, I forget if the unity had temperature,
I'd never use that feature, I mean even at work on my flukes, I don't check the temperature
of anything, but there you go, you got temperature and you got some probes, I don't know if they're
k type or what, but I got some temperature probes, no, actually that would come in handy
because I was recently trying to troubleshoot a board and I had a feeling that something
was overheating and then causing a chip to go crazy, so maybe that, maybe I should look
into maybe the spec sheet of that chip and that component will tell me what temperature
should operate at and I can watch it with a meter and the temperature probe and see if
it exceeds its specifications, okay, next one is micro amps, milli amps and amps, what does
it have for amps, whoa, it says you can put this thing in with 20 amps of current at 250
volts going through the meter, that's, I'm going to have to open this up later and check
the fuses and stuff, that's substantial, each 15 minute max, 10 seconds, maximum 20 amps
at 250 volts, which is huge, each 15 minutes max on 10 seconds, okay, so they want you to,
you can check 20 amps worth of current going through this little cheap $30 meter and
you can check it only for 10 seconds and then you'll have to let the meter cool down
for 15 minutes, okay, this is interesting, oh let me put the thing aside, okay, another
thing this has, which I really like is a backlight, let me see if it works, oh that's hold
if you want one and if I long hold, yeah, nice little, I'll take a picture there, it's
nice little, looks white, almost kind of a bluish white, it looks good, let me take this
screen protector off, oh and well by the time I got the camera the light went out so it
doesn't stay on for very long, there we go, maybe like 10 seconds and what's this other
button, oh the other button is Bluetooth, there's two blue buttons, one is light and hold,
one is Bluetooth, so I think what I'll do is, I'll turn on my Keith Lee, I'll turn
on my Keith Lee 2110 bench meter, I'll turn on the Unity and I'll turn on this O-On and
I'll run them, I'll turn on the bench power supply and I'll take some readings with
all three of them and see how they do with, you know, I'll run the bench power supply
up from zero to 30 volts and then we can, I'll get my decade resistance box and I can
check out some resistance and I have some capacitive settings so let me see how they all
stack up together, got to power everything on, I have to go find my probes for the Unity
because it was in a bag, oh that was the reason I was having trouble getting the O-On's
probe protectors off, probe protectors a little cap that goes over the like three quarters
of an inch of the metal probe and just lets a little tip stick out, so if you're in something
delicate, you're on like an IC, you're in there, you just want to probe with the very tip,
you don't want to lay your three quarters of an inch of metal down in there somewhere
and short something out to a capacitor or what have you, so the probe protectors, they
screw in as well to that threaded insert, that's good. That's the Unity coming on, the
Keith Lee is ready, my bench power supply just happens to be set at 9.3 volts from a project
I was working on recently, so let me see, connect up the Unity, connect up the O-On, now I have
way too many leads and they're all braiding together, I can tell I'm going to have to cut out some
silence in this one, oh that's weird, I'm pushing in on the O-On, I'm pushing the probe in and it doesn't
feel very good, you really have to push in quite hard, that's, well that's, that's so great,
oh I'm really shoving that in there, yeah this is a fail here,
wow something about these O-On probes, oh it might be the socket on the O-On it's so, yes that's
me banging on the meter, oh kidding, I think the probes are a failure, the black probe will not go in,
it's like it's too fat,
I'm going to have to get other probes, I wonder if this will fit in the Keith Lee, no, there's a fit in the Unity, yes,
but I think the Unity has a split barrel, it does, inside there's a split barrel on the Unity to accept the
the male end of the probe, I bet the O-On does not have a split barrel and the male end of this
black probe is too fat to fit in there, I was really squeezing on it, I'll have to look at that more
later but for now I'm going to get another set of probes, let's try these X-Tech ones that I like,
yeah they fit in their tight, tight is good, but oh my goodness those other probes were bad,
now I'll get the alligator clips for the, oh these X-Tech probes that I like, maybe I'll take a
picture of these, I'll take a picture of the three different styles of probes,
well this is going to get confusing, I have way too many probes on the table here, okay I'll take a
picture of this, but you actually get to, here the pictures being taken as well, okay if you
look at this picture I'll post it up on the left is the O-On probe and if you can see the like
three quarters of an inch of the probe, the business end of it at the bottom is about a quarter inch
of threads and that's what's going to hold the alligator clip and the probe protectors on,
the next one over the darker red is the X-Tech ones that I like, oh I should show you that too, let me
pull that off, here I'll take a second picture like this,
the second picture with my thumb in there is showing that X-Tech probe as well and what it is
is you can pull the probe apart and what you have is another banana connector that can,
so you can couple two meters together or you can get an accessory like the, let me take another
picture, there you go, so I'm holding the banana connector of the probe and it just came out,
you can see the probe right underneath it, next to that is another insert that will go in and turn
the probe into a little mini pincer for getting on like a IC or a very small component,
a little tiny alligator clip and then somewhere around here which I don't know where they are,
oh is another accessory you can stick on there, so I'm putting the probe part back into the
banana socket which could like I said you can daisy chain meters with this and then if you look
at the tip of it you can see it's got like a flared out piece that spins around and what that is
is like a banana clip, it's like another banana clip, so you can just stick that right into a meter
and go right in, you can stick your probe tip into a meter socket if any of that makes any sense,
so we'll go back to that previous picture, so on the left was my Keetley, I hope,
that's what I had, no it didn't, let me put him back the way they were,
so I described them correctly,
there it is, so the left was the O-on with the threaded insert type probe, the next one was the
X-tech that had the, it can come apart and you know become a socket to go into another meter or
it has the little banana clip on the probe that you can actually probe into another socket,
the next one over is my Keetley bench meter, this is a, they shroud the probe, if you look at it,
it should be like a three quarters of a piece of metal probe there but they have it shrouded in
that plastic, so this one you have no choice but to just probe little things, you just probe exactly
what you want, you know, if you need more probe on your probe, more metal, you go get something else,
these are nice probes, and the last one is the ones that come with the unity, they do have a little
bit of probe shielding like built in like the Keetley but then they still stick out three quarters
of an inch of you know metal there, so I don't know why they do that, okay back to where I was,
we're gonna check voltage, oh as I'm doing it, the X-tech that little flared out,
piece on the probe that I said you can also stick into a meter, that grabs their alligator clip
accessory as well, so I just slid the alligator clips onto it, and these alligator clips are nice,
they shield right up through the whole entire tip of the alligator, I should probably put a link
to this set in the show notes because it's only like 15 bucks and it's a pretty good set of probes,
okay there's two meters hooked up and I'll just hold the probes on the Keetley,
so power supply is at 9.3 volts DC, unity is 9.324, the all on is 9.30, so it's
kind of showing a discrepancy, the Keetley would, let's say the Keetley is gonna be the bench
standard here because that's gonna be the best meter on the bench, Keetley is showing
hold the probes in the right hand, I was staring at the Keetley wondering why it's giving me
negative voltage, I had the black and the red in the wrong hand, okay, let's go back again, unity
9.324, and as you can see I'm saying the 0.324, I'm gonna get to that later, that's why the unity
is still gonna win for me, you can see it has more resolution, oh on, 9.30, there's a discrepancy
and the Keetley, which is gonna be the bench standard for this bench because it's pretty good
meter, 9.3248, so again the unity is like spot on, the Keetley I know is gonna be pretty darn good,
the all on is showing low, try another range, I'll go course, let's go something lower,
I got 1.4 volts DC, I'll check these out, the unity is showing 1.395, so that's 1.4, just round up,
that 9's gotta go up and that, yep, it just got to it, 1.400, unity spot on, the all on is 1.399,
which, and it just came up to 4, and if the 9 you're round up, so that's right on,
and the Keetley is bang on 1.400, let's go, maybe it's having a little trouble with it, let's go to
a higher voltage, let's go right up to 30, okay my bench power supply, which is 0 to 30 volts DC,
it's maxing out at 31.4 volts, so oh I just switched the probes again in my hand,
let's see what this does, unity 3142, oh on, 3137, and the Keetley 3144, so Keetley unity spot on,
wow this is a lot of probes on the table, what am I doing here?
okay, I have, what is something beeping at me for?
Ah, I think the all on just beeped at me because I'm in the wrong measurement, I still have it in
voltage DC, and I think it knows I just hooked up a resistive load, and it's beeping that I'm in the
wrong setting, which is good, so let me go up to ohms, ohms on the oh on, set the Keetley to
ohms 2-wire, and what is the substitution box on, let's go, that should be 200k right there,
the unity is showing 2.10, so 2k, the oh on is bouncing all over like a madman,
I wonder if I'm getting interference from the other meters, I should try these all just singly,
okay my decade resistance box is not the best, I'm sure these are not precision resistors, this
was another kit, these I should have done, oh there's another HPR maybe, I can tell about the
decade resistor box and the decade capacitor box that I built, just for obuse these are not
precision, I have the, I have 100k dialed in on the substitution box, let's see what the
Keetley says, Keetley says, 98.8 ohms, so that's pretty good, there we are, the ohms says,
oh on says, 98.8, the unity says,
98.7, this is all good, this is all within range, let's go up to a thousand k,
I'll go backwards now because I have the probes in my hand, unity 0.99 mag,
that's good, oh on, this is a lot of probes,
0.997 mag and be Keetley, 0.997, okay resistance is pretty good, okay that's a pass,
the voltage, we still had some little problems, the resolution, I should talk about that on the
oh on, they say it's three and five sixth, what do they call it, it's crazy, three and five sixth
display, I don't even know what that is, but the nearest I could do calculating that to counts is
it's a 6,000 count meter, the unity is a 22,000 count meter, you're going to get more resolution,
if you heard me back then I was saying this has 0.000, 0.1, you know blah blah blah, it had three
digits of resolution behind the decimal point, my Keetley 2110 is a five and a half digit meter
and that would give you four, blah blah blah blah, you know, or did I do four blocks there,
you got to count, go back and count them, it'll give you more resolution, so up the three meters
on the bench, Keetley has the most resolution, next up is the unity and least is the on,
now I think I have to go download the app and see if this bluetooth stuff works, which is the
whole reason they got 35 bucks out of my pocket, oh before I do the bluetooth I just remembered I
didn't do the continuity test, which is pretty important for a meter, oh I'm already in the home,
so let me go in the homes, and another thing I'm going to do, I didn't read the manual, but I don't
know if this has an auto time off, an auto shut off, which I find really handy, so I'm just going to
leave this meter run for, you know, 20 minutes while I'm trying to download this bluetooth stuff,
if it takes that long, and see if it auto times out, so continuity, let's go up to homes, select,
this diode test, continuity, so let's see how quick it is,
it's reasonably click, it's reasonable, it's not a fluke, let me see my,
Keetley here,
see my Keetley, as soon as you touch it, bang, it goes, I don't have my fluke here to work,
this one has a little delay in it, this will probably be better as a video, but let me see the,
I know I've done the unity before, but let me see how it compares with the oh on here, let me go to,
oh unity wins again, that's, you know what, that's faster than my Keetley,
now it's about on par, again the unity, it just surprises me, the meter you get for the money,
the continuity is really good, the oh on takes just this little split second when you touch
the probes together to register, but it's a good clear beep, the reason you want a really fast
continuity is let's say you're having a trouble with a board, and you know you're having trouble
at this, this wire that leaves the board right here, but you don't know where that wire goes on
the whole entire board, it might go up to a you know quad flat pack, I see that's got you know
300 connections on it, and what you want to do is hold the probe on the bad wire,
go up to that flat pack and just drag your probe along all those hundreds and hundreds of connections,
and you want a fast continuity because as you drag you don't want to drag like, you don't
want to take 10 minutes, you want to go pretty fast and you want it to pick up
quickly like right where this wire goes to this connection on this I see or vice versa, you know,
probing around looking for a resistor or what have you, faster is better,
but this is this oh on is acceptable, and it latches and it's not scratchy, so not bad, but again
the unity's beating it, I know my flute beats it, this cutely beats it, but again we're talking
about a $35 meter, so all right now I'm going to go get the Bluetooth stuff,
okay I have it downloaded, it wasn't clear looking through the manual where to get the
download from, and then I notice on the back of the manual it has a QR code, so I just scanned
that, scanned that, and it took me right to the Bluetooth section of their web page, and I downloaded
the, here it is, BT, which one do I want to install? I download it too because I wasn't sure which one
to use, I think it's going to be this one, so let me install it on known sources, let it through,
I hope this is not installing back doors on my phone because this stuff is from who knows where,
app installed, open, oh look at that, it says no device, no, I'll take a picture of this,
oh that was easy, it's an easy install, let's see how it works, so there's,
it says no input, no input, no device, no device, so now I guess I'd have to do some pairing,
it says to hold down this, oh I just lost it, there it go, multimeter, hold down the Bluetooth
button on the O-on, settings, Bluetooth, pair with the device, scan, O-on, B-35T, there it is,
I'll click select that, pairing, just letting you know, I mean I'm doing this live so you can
see if it's a pain in the butt or not, while it's pairing I'm looking at the O-on,
1000 volts, cat 3 rated, for a 35-dollar meter,
I'm able to communicate with O-on B, so let me go back to the instructions,
I'm flipping through the instructions, they don't call it continuity, they call it a buzzer feature,
you'll have a buzzer feature, okay, I cannot get this to pair so far, this is going to take some
troubleshooting, it might be something I'm doing wrong, error, I'm able to communicate with O-on
B-35T, I turned on make row gaxes point, but visible value, row gaxes point is the name of my
Bluetooth, so anybody scanning for Bluetooth in a coffee shop or something is not going to want to
click on row gaxes point, that's my phone, I made it visible, I click on the O-on, it tries to pair
and it does not pair, so I think this is going to be a two-part HPR because I've gone on long
enough, I'm going to try and get this to pair, I'm going to do some troubleshooting online, I'll let
you know what I found, I'll let you know if it was my fault or if it's a fault with a meter,
I'm sure it's just something I'm doing wrong, and then in that second part what I'm going to do
is take this meter apart and have a look inside, look you know they're saying thousand volt cat three
and you have a buzzer, so let's take a look inside this meter and see how it's built, see how the
fuses are, see if there's any protection in there or you know the cutouts on the board and all that
stuff, so okay we'll get two HPRs out of this, so if anybody wants to contact me, I know I've been
like quiet lately on the social internet because our company, our family business merged in with a
larger company, so I have more responsibilities now and you know I have people I need to work with
and stuff, so I'm not like around the computer as much as I used to be, so I'm not you know just
constantly you know denting people and stuff like that, but I'm still alive, so I'm still around on
GNU social slash, identical stuff as NY bill at smy, yeah, NY bill at sn.commonkeynet.net and email
is still NY bill at gummonkeynet.net and I will check the comments and we can have a conversation
in there if you like, so until part two of this meter review, I will talk to you guys later.
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