Tektronix THS7xxx Scope Hack/Teardown/Discussion - FW 1.16 found

[Zucca]

The mod and the update are gone perfectly and also after running the offset compensation just one time after the update the dc issue wanishes completly. No recal.

Ciao Giacomo,
so you did not perform a full calibration after the upgrade? Are you sure it is still in spec?
AFAIK the cal parameters are stored in the AM29F080, and you should have the calibration parameters of yaromka in your unit...

[harrimansat]

Can you please share 1.14 firmware?

Thanks

[giacomo]

The mod and the update are gone perfectly and also after running the offset compensation just one time after the update the dc issue wanishes completly. No recal.

Ciao Giacomo,
so you did not perform a full calibration after the upgrade? Are you sure it is still in spec?
AFAIK the cal parameters are stored in the AM29F080, and you should have the calibration parameters of yaromka in your unit...

I can't say that, for now i only tried the square signal for the probe compensation. I was interested to elinate the dc issue and i reported that once it has been disappear. So i screwed up the calibration in my unit without thinking about..

By the way when i turned on the scope after the upgrade to the 1.16 the dc issue was still present as before, but this time the signal path compensation has worked, once and for all it seems, before it did not correct the problem.

Can you please share 1.14 firmware?

Thanks

Why you would the 1.14 when you can get the 1.16 ? I had the 1.11 if you was asking to me

[harrimansat]

The mod and the update are gone perfectly and also after running the offset compensation just one time after the update the dc issue wanishes completly. No recal.

Ciao Giacomo,
so you did not perform a full calibration after the upgrade? Are you sure it is still in spec?
AFAIK the cal parameters are stored in the AM29F080, and you should have the calibration parameters of yaromka in your unit...

I can't say that, for now i only tried the signal for the probe compensation. I was interested to elinate the dc issue and i reported that once it has been disappear. So i screwed up the calibration in my unit without thinking about..

By the way when i turned on the scope after the upgrade to the 1.16 the dc issue was still present as before, but this time the signal path compensation has worked, once and for all it seems, before it did not correct the problem.

Can you please share 1.14 firmware?

Thanks

Why you would the 1.14 when you can get the 1.16 ? I had the 1.11 if you was asking to me

hi, can you please share 1.14 firmware?

Thanks

[Zucca]

Why you would the 1.14 when you can get the 1.16 ? I had the 1.11 if you was asking to me

Yeah, if you don't tell us why we will not give you the 1.14   

[giacomo]

i got in contact with the harrimansat and even the 1.11 is ok for him, so i sent it in private

But since my unit has been purchase as not working due to the dc issue, as first guess, my firmware would bring the problem back, so i am not sharing it in the forum, it could be a sorce of throuble if someone read the thread too fast and flash his unit with my firmware

[Zucca]

Thanks Giacomo,

I forgot to welcome you to this amazing forum. I fully agree with you.
Well done bro.

[harrimansat]

Thanks, it will be interesting to have more dumps to knob where is calibration data

[superman13]

Thanks, it will be interesting to have more dumps to knob where is calibration data

For this we should get same version of firmware from different samples...

Or if someone can perform calibration process and provide an Dump before and after...

[giacomo]

Here is the 1.11 that was in the 710a with the dc problem

[1audio]

My backlight is very dimmed, I believe the lamp is showing its age. Does anyone have replaced the lamp or added a LED upgrade?

I have done both now. Unfortunately the LED is not much brighter than the CCFL lamp. The LCD and optics just are not that bright. However it is a transreflective display so you can see it with the lamp off but in bright light it's not easy to read. I have the two side by side. Its useable but nowhere near as readable as a current LCD scope display. I would just put a new lamp in (cheap and not hard) and move on.

[jal1234]

Could somebody who has a pair of calipers do some measurements on the battery door/lid/cap that holds the battery pack in? Mine is missing on my THS720a. I have the metal piece that latches into place, but I'm completely missing the rest of it. I assume there is a groove for an oring to seal the compartment, but I'm not sure. A rough drawing with measurements would be ideal. I was hoping someone might have a 3D printed version, but I haven't been able to find anything.
Thanks in advance.

[Gae]

Yeah !
What a great post about this scope !

I have a question about this scope: I could buy one for about 260€, seeing it's a quite "old" design (from the 90's ?) is it worth to get it at this price ? They sell it on "good conditions" with very little use... but of course batteries will be maybe out of order ... and I see they have quite a problem with expensive replacement.
The use will be mainly for audio, don't really need 100MHz but a handled scope is functional for me becouse I may have to repair "in situ" some times.

I have an Hantek DSO8060 but I don't think it's a good scope, the screem is not very accurate and I have problems with after just a few month of use...

Thanks for your help.

[HighVoltage]

Yeah !
What a great post about this scope !

I have a question about this scope: I could buy one for about 260€, seeing it's a quite "old" design (from the 90's ?) is it worth to get it at this price ? They sell it on "good conditions" with very little use... but of course batteries will be maybe out of order ... and I see they have quite a problem with expensive replacement.
The use will be mainly for audio, don't really need 100MHz but a handled scope is functional for me becouse I may have to repair "in situ" some times.

I have an Hantek DSO8060 but I don't think it's a good scope, the screem is not very accurate and I have problems with after just a few month of use...

Thanks for your help.

At 260 Euro in good condition it is still a good scope to have, if you need a portable scope.
Depending on the model you even get two isolated channels and that is a big benefit as well for some applications.

I am still using my THS720p on a regular basis, although I probably have plenty of other and modern scopes.

[BravoV]

The major values of this scope are portable and fully isolated at each channel that are suitable for HV works.

If you're buying this at the price, just for low voltage probing as common usage to replace you current Hantek, then I think its a bit of waste, as that kind of money can be used to buy new and more decent or much better DSO.

Also you must take note especially with this scope, you have to use with the HV probes in order to use it at HV probing as where it good at, and these alone if the seller does not supply it, these HV probes, even the Chinese made ones are not that cheap either compared to ordinary cheap x10 scope's probes.

For sure its out of warranty already.

Edit : Almost forgot, the LCD backlight is NOT LED based (CFL), which has much higher risk that it will be dead at anytime soon.

[Zucca]

The major values of this scope are portable and fully isolated at each channel that are suitable for HV works.

This! +1000 times! Very important point!

[Gae]

Many thanks for the comments.

Yes, I agree, I already have a DSO scope (not very good) and I'll save for a analogic one.

Maybe an Hameg HM408 or a Tek 453 or a Philips PM3267 at about 100€. Witch one would be most recommandable for audio repair only ?
 

[r_anton]

Hello all
I've bought THS730 version of the scope and after successful calibration it shows a ripple about 40mV peak-to-peak and the DC offset flows with time between -20..+20mV

Is any way to improve it ?

Thank you

[harrimansat]

Hello all
I've bought THS730 version of the scope and after successful calibration it shows a ripple about 40mV peak-to-peak and the DC offset flows with time between -20..+20mV

Is any way to improve it ?

Thank you

I will test with mine, can you please upolado some photos, whic is noise frequency?

[r_anton]

I will test with mine, can you please upolado some photos, whic is noise frequency?

Hello

These are the photos without and with probe
FV:v1.14

Thanx for reply

[harrimansat]

I will test with mine, can you please upolado some photos, whic is noise frequency?

Hello

These are the photos without and with probe
FV:v1.14

Thanx for reply

Do you have more noise without probe?

[r_anton]

Do you have more noise without probe?

a little bit more without probe and it has a kind of periodic type, with probe it become random. What is strange, like on the second foto, I don't see on the wave form measured peak-to-peak value of 23mV (often it's 40mV)

[harrimansat]

Do you have more noise without probe?

a little bit more without probe and it has a kind of periodic type, with probe it become random. What is strange, like on the second foto, I don't see on the wave form measured peak-to-peak value of 23mV (often it's 40mV)

Can you please make the same test in AC, and GND, and then shorted?

[r_anton]

Can you please make the same test in AC, and GND, and then shorted?

Of course, thanx for helping

[harrimansat]

Mine has the same behaviour:

If scope don´t meassure nothing with shorted inputs, it usually means it's ok.

Think that this scope has isolated gnd and it has more noise when then are not connected