Tonghui TH2821A LCR Meter

On 10/31/2011 9:58 PM, Mike wrote:
> Here's something that may interest some folks here. I just got my new
> Tonghui TH2821A LCR Meter, and I'm starting to become quite impressed.

> Regards,
>
> Mike

Hey, Mike -

How long did it take to get your meter?

John S

John S <sophi.2@invalid.org> wrote:
 
> Hey, Mike -
> 
> How long did it take to get your meter?
 
> John S

I ordered it on Thu, 8 Sep 2011, it was shipped within a day or so, and it 
arrived on Mon, 3 Oct 2011. 

That is about normal for shipments from China to Ontario, Canada. You will 
probably see faster delivery in the US. I forget which delivery service 
they used. Maybe it was DHL.

I really like the dissipation factor on electrolytics. You don't have to 
measure the ESR, then go to a lookup table to figure out if that is the 
proper value for the capacitance. 

I just look at the dissipation factor, and if it's greater than about 0.2 
for an older cap, toss it. This is a big time saver.

Mike

On 11/8/2011 4:29 PM, Mike wrote:
> John S<sophi.2@invalid.org>  wrote:
>
>> Hey, Mike -
>>
>> How long did it take to get your meter?
>
>> John S
>
> I ordered it on Thu, 8 Sep 2011, it was shipped within a day or so, and it
> arrived on Mon, 3 Oct 2011.
>
> That is about normal for shipments from China to Ontario, Canada. You will
> probably see faster delivery in the US. I forget which delivery service
> they used. Maybe it was DHL.
>
> I really like the dissipation factor on electrolytics. You don't have to
> measure the ESR, then go to a lookup table to figure out if that is the
> proper value for the capacitance.
>
> I just look at the dissipation factor, and if it's greater than about 0.2
> for an older cap, toss it. This is a big time saver.
>
> Mike

Great info on delivery AND dissipation. Many thanks.

Cheers,
John S

John S <sophi.2@invalid.org> wrote:

> Great info on delivery AND dissipation. Many thanks.
> 
> Cheers,
> John S

I really think the numbers it gives are quite believable. I just measured 
some film capacitors, and the larger ones gave dissipation factors around 
0.001 to 0.0005, which corresponds to a Q of 1,000 t0 2,000.

A very small 1.5 nF gave D=0.0002, for a Q of 5,000. That seems a bit high, 
but still in the realm of possibility when you consider that is the least 
significant digit.

I'm very happy with it so far. Works great, and it autoscales and gives the 
reading very fast. This instrument will not slow you down, unless you 
forget to discharge a large cap before connecting it to the meter.

Mike

On 11/8/2011 4:51 PM, Mike wrote:
> John S<sophi.2@invalid.org>  wrote:
>
>> Great info on delivery AND dissipation. Many thanks.
>>
>> Cheers,
>> John S
>
> I really think the numbers it gives are quite believable. I just measured
> some film capacitors, and the larger ones gave dissipation factors around
> 0.001 to 0.0005, which corresponds to a Q of 1,000 t0 2,000.
>
> A very small 1.5 nF gave D=0.0002, for a Q of 5,000. That seems a bit high,
> but still in the realm of possibility when you consider that is the least
> significant digit.

It depends on the dielectric material. NP0 (C0G) has the lowest D of the 
ceramics based on my limited experience. If the one you measured is not 
NP0 (C0G) then, yes, the Q reading may be high.

> I'm very happy with it so far. Works great, and it autoscales and gives the
> reading very fast. This instrument will not slow you down, unless you
> forget to discharge a large cap before connecting it to the meter.
>
> Mike

As I said, the specs look great. I'm anxious to get my hands on it. The 
instruments I have now put out too much voltage to measure components 
in-circuit, so I'm hoping this will help.

Thanks for the additional info.

Cheers,
John

John S <sophi.2@invalid.org> wrote:
 
> As I said, the specs look great. I'm anxious to get my hands on it.
> The instruments I have now put out too much voltage to measure
> components in-circuit, so I'm hoping this will help.
 
> Thanks for the additional info.
 
> Cheers,
> John

It doesn't seem to mind having a diode across an electrolytic, but I 
haven't tried that with lower values like 1 nF.

Let me know what you think of it when you get yours. It would be 
interesting to compare notes. But it sure beats the pants off the Capacitor 
Wizard, at$229.95:

http://midwestdevices.com/

or $189.95:

http://www.howardelectronics.com/ieinc/cwinfo.html
 
Mike

On 11/8/2011 6:03 PM, Mike wrote:
> John S<sophi.2@invalid.org>  wrote:
>
>> As I said, the specs look great. I'm anxious to get my hands on it.
>> The instruments I have now put out too much voltage to measure
>> components in-circuit, so I'm hoping this will help.
>
>> Thanks for the additional info.
>
>> Cheers,
>> John
>
> It doesn't seem to mind having a diode across an electrolytic, but I
> haven't tried that with lower values like 1 nF.
>
> Let me know what you think of it when you get yours. It would be
> interesting to compare notes. But it sure beats the pants off the Capacitor
> Wizard, at$229.95:

I will.

Errr... The Wizard only tests ESR, yes? I don't think a comparison is 
possible under the circumstances.


> http://midwestdevices.com/
>
> or $189.95:
>
> http://www.howardelectronics.com/ieinc/cwinfo.html
>
> Mike

If the TH2821A performs to the specs, then the money is minor and the 
Wizard looses miserably.

John S

On Tue, 08 Nov 2011 22:29:40 GMT, Mike <spam@me.not> wrote:

>
>John S <sophi.2@invalid.org> wrote:
> 
>> Hey, Mike -
>> 
>> How long did it take to get your meter?
> 
>> John S
>
>I ordered it on Thu, 8 Sep 2011, it was shipped within a day or so, and it 
>arrived on Mon, 3 Oct 2011. 
>
>That is about normal for shipments from China to Ontario, Canada. You will 
>probably see faster delivery in the US. I forget which delivery service 
>they used. Maybe it was DHL.

Slow boat.  ;-)  I had a laptop (Lenovo) shipped from China on a Monday (China
time) and it was delivered on that Wednesday, noonish, to my home in Alabama.
It came UPS. 

krw wrote in message news:ciljb7p5u16k66jutpaok8dn0jlsrb92eg@4ax.com...

> Slow boat.  ;-)  I had a laptop (Lenovo) shipped from China on a =
Monday
> (China time) and it was delivered on that Wednesday, noonish, to my
> home in Alabama.
> It came UPS.

Just yesterday I received a DSP shortwave radio I ordered from (I think) =
the=20
same supplier.
http://www.ebay.com/itm/190452362072?ssPageName=3DSTRK:MEWNX:IT&_trksid=3D=
p3984.m1439.l2649
I ordered it 10/25, so that was less than 2 weeks. It came via USPS.=20
Supposedly air mail.

It's a pretty nice radio, but all the labels and instructions are in=20
Chinese. I asked for a translation, but I figured out how most of the=20
functions work. Not bad for $24 total including shipping.

I'm still waiting on some other items. And I found that they play games =
with=20
pricing and shipping. For instance, I've seen something for about $20, =
with=20
free shipping. And then I found the same item for $0.99, with $19 =
shipping.

I use www.pcbcart.com for my PC boards, and they usually arrive about a =
week=20
after ordering.

Thanks (to Mike, I guess) for the alert to these bargains. I might order =

some other things. Their USB 200x microscopes sound interesting.

Paul=20

"krw@att.bizzzzzzzzzzzz" <krw@att.bizzzzzzzzzzzz> wrote:

> On Tue, 08 Nov 2011 22:29:40 GMT, Mike <spam@me.not> wrote:
> 
>>
>>John S <sophi.2@invalid.org> wrote:
>> 
>>> Hey, Mike -
>>> 
>>> How long did it take to get your meter?
>> 
>>> John S
>>
>>I ordered it on Thu, 8 Sep 2011, it was shipped within a day or so,
>>and it arrived on Mon, 3 Oct 2011. 
>>
>>That is about normal for shipments from China to Ontario, Canada. You
>>will probably see faster delivery in the US. I forget which delivery
>>service they used. Maybe it was DHL. 
> 
> Slow boat.  ;-)  I had a laptop (Lenovo) shipped from China on a
> Monday (China time) and it was delivered on that Wednesday, noonish,
> to my home in Alabama. It came UPS. 

I am in Canada, the land of polar bears and dog sleds. It snows here.

I just ordered the top853 USB universal programmer mentioned by Nico 
Coesel, http://www.ebay.com/itm/160378432470

I just received the following email from them:

  We shipped YOUR item from our office today.

  1)If you  are  in United States, we ship your order  via  USPS First
  Class mail  Internationl. The estimated the delivery  time  is about
  7~10 days.

  2)If you  are  outside  of United States,  we  ship  your  order via
  standard air mail.

  The delivery  shipping  time is about 20~35 days  according  to your
  countries.

I lived in the States for 30 years before returning to Canada. I sure 
miss the fast postal service you have down there. A letter across town 
usually went overnight. Here, it takes 5 business days. That means you 
have to add two more days for the weekend:)

Mike