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Yesterday I picked up from eBay a Type 106 High Amplitude (120v into 50ohm), Fast Rise Square Wave Generator. I haven¡¯t received it from Germany yet. I¡¯m wondering whether I should keep the original low reflection GR-874, and get a GR-874 to BNC adaptor for it, or convert it to BNC¡¯s. I know the Fast Rise outputs are mounted on the board, probably to further minimize the reflection, and are harder to convert. But wouldn¡¯t a BNC adapter, like a conversion to BNC, defeat the purpose, and add reflection?? Also, it comes in a rather unusual (to me) case, which does appear to be stock. /g/TekScopes/album?id=261997
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I kept the gr connectors on the fast rise but good quality bnc is good to 4
Ghz so I changed the high output one for ease of hookup. Just needed a
quick adaptor plate.
Eric
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On Thu, Mar 18, 2021, 10:02 AM Stephen <stephen.nabet@...> wrote: Yesterday I picked up from eBay a Type 106 High Amplitude (120v into
50ohm), Fast Rise Square Wave Generator.
I haven¡¯t received it from Germany yet.
I¡¯m wondering whether I should keep the original low reflection GR-874,
and get a GR-874 to BNC adaptor for it, or convert it to BNC¡¯s. I know the
Fast Rise outputs are mounted on the board, probably to further minimize
the reflection, and are harder to convert.
But wouldn¡¯t a BNC adapter, like a conversion to BNC, defeat the purpose,
and add reflection??
Also, it comes in a rather unusual (to me) case, which does appear to be
stock.
/g/TekScopes/album?id=261997
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BTW, while researching this, I noticed a small error on the TekWiki page.
It states the following:
¡° High Amplitude Output: 12 V into 50 ¦¸ load, 12 ns rise time, 600 ¦¸ output impedance, GR-874 connector¡±
It¡¯s should be 120V, not 12V...
I don¡¯t know if someone here has access to correct the page, but I just thought I¡¯d mention it.
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On Thu, Mar 18, 2021 at 03:07 PM, Stephen wrote:
It¡¯s should be 120V, not 12V...
I don¡¯t know if someone here has access to correct the page, but I just
thought I¡¯d mention it.
According to the specifications (Tek catalog 1970), 12V is the correct value. You have to realize that with a duty cycle around 50% (the 106 goes from less than 45% to more than 55%), average *output* power would be above 140W! And that with a rise time of 12ns? Nice! Raymond
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On Thu, Mar 18, 2021 at 03:21 AM, Raymond Domp Frank wrote:
On Thu, Mar 18, 2021 at 03:07 PM, Stephen wrote:
It¡¯s should be 120V, not 12V...
I don¡¯t know if someone here has access to correct the page, but I just
thought I¡¯d mention it.
According to the specifications (Tek catalog 1970), 12V is the correct value.
You have to realize that with a duty cycle around 50% (the 106 goes from less
than 45% to more than 55%), average *output* power would be above 140W! And
that with a rise time of 12ns? Nice!
Raymond
Raymond, I read what¡®s written on the machine... >= 120V, <12ns into 50ohms. Forgive my lack of knowledge, or maybe my lack of understanding, but would 12V be considered ¡°High Amplitude¡±?
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Look at the manual, page 1-4. It lists both > 12v and > 120v depending on the termination (this does seem odd to me).
DaveD
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On Mar 18, 2021, at 11:01, Stephen <stephen.nabet@...> wrote:
On Thu, Mar 18, 2021 at 03:21 AM, Raymond Domp Frank wrote:
On Thu, Mar 18, 2021 at 03:07 PM, Stephen wrote:
It¡¯s should be 120V, not 12V...
I don¡¯t know if someone here has access to correct the page, but I just
thought I¡¯d mention it.
According to the specifications (Tek catalog 1970), 12V is the correct value.
You have to realize that with a duty cycle around 50% (the 106 goes from less
than 45% to more than 55%), average *output* power would be above 140W! And
that with a rise time of 12ns? Nice!
Raymond
Raymond,
I read what¡®s written on the machine... >= 120V, <12ns into 50ohms.
Forgive my lack of knowledge, or maybe my lack of understanding, but would 12V be considered ¡°High Amplitude¡±?
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There is not a lot of drive behind the signal. It is generated by 4 tubes
in parallel so impedance mismatches will do very strange things. Properly
terminated it will put out 100 volt + square Waves mine hits about 108. It
can be used to drive the tunnel diode pulser for scope calibration. Use
mine all the time.
Eric.
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On Thu, Mar 18, 2021, 11:07 AM Dave Daniel <kc0wjn@...> wrote: Look at the manual, page 1-4. It lists both > 12v and > 120v depending on
the termination (this does seem odd to me).
DaveD
On Mar 18, 2021, at 11:01, Stephen <stephen.nabet@...> wrote:
On Thu, Mar 18, 2021 at 03:21 AM, Raymond Domp Frank wrote:
On Thu, Mar 18, 2021 at 03:07 PM, Stephen wrote:
It¡¯s should be 120V, not 12V...
I don¡¯t know if someone here has access to correct the page, but I just
thought I¡¯d mention it.
According to the specifications (Tek catalog 1970), 12V is the correct value.
You have to realize that with a duty cycle around 50% (the 106 goes
from less
than 45% to more than 55%), average *output* power would be above 140W!
And
that with a rise time of 12ns? Nice!
Raymond
Raymond,
I read what¡®s written on the machine... >= 120V, <12ns into 50ohms.
Forgive my lack of knowledge, or maybe my lack of understanding, but
would 12V be considered ¡°High Amplitude¡±?
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On Thu, Mar 18, 2021 at 04:07 PM, Dave Daniel wrote:
Look at the manual, page 1-4. It lists both > 12v and > 120v depending on the
termination (this does seem odd to me).
Nothing odd about that. It's (max) 12V into 50 Ohm, (max) 120V unloaded. Many generators have an output impedance of 50 Ohm. Output voltage halves when loaded by 50 Ohm, compared to open-ended. Faster ones are spec'ed at 50 Ohm load. The high-amplitude output of the PG506 reaches > 100V open-ended and about 5 .. 6V into 50 Ohm, if I remember well. The high-amplitude output of the PG506, and apparently, the Type 106, may be used with Tek's tunnel diode pulser, as Eric describes. Raymond
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To be honest, I haven¡¯t had a look at the manual yet. It just seemed odd to me, while reading the page, that only 12V would be called ¡°High Amplitude¡± while the front panel states 120V, which is more what I would call ¡°High Amplitude¡±.
If the manual deemed worth to mention both voltages and pointing out the differences, maybe, for exactitude sake, Tek-Wiki should mention it too. That¡¯s all I¡¯m suggesting...
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On Thu, Mar 18, 2021 at 04:26 AM, Raymond Domp Frank wrote:
On Thu, Mar 18, 2021 at 04:07 PM, Dave Daniel wrote:
Look at the manual, page 1-4. It lists both > 12v and > 120v depending on
the
termination (this does seem odd to me).
Nothing odd about that. It's (max) 12V into 50 Ohm, (max) 120V unloaded.
Many generators have an output impedance of 50 Ohm. Output voltage halves when
loaded by 50 Ohm, compared to open-ended. Faster ones are spec'ed at 50 Ohm
load.
The high-amplitude output of the PG506 reaches > 100V open-ended and about 5
.. 6V into 50 Ohm, if I remember well.
The high-amplitude output of the PG506, and apparently, the Type 106, may be
used with Tek's tunnel diode pulser, as Eric describes.
Raymond
Thank you for the explanation.
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On Thu, Mar 18, 2021 at 03:06 PM, Eric wrote:
but good quality bnc is good to 4
Ghz
You do need very good BNC (cables, connectors, constant contact surfaces) to get even close to that. Even good quality BNC tends to be visibly inferior above 500 - 800 MHz. I'd rather leave GR874 on and use a converter plug to BNC or a GRC-to-BNC cable when needed. OTOH, it's "only" a 12ns edge and with a pulse generator, amplitude loss is less important than correct and constant impedance all-through but even then I'd see no reason not to leave things as they are and use a converter plug. Raymond
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The PG506 some times will not have enough drive current to trip the tunnel diode in the pulser, It can be hit and miss especially with the ageing of the pulser diodes I have not had any issues with the 106. But I also need to state I have a sample size of 1. However my PG506 cant quite get the diode to trip so I have to use the 106. The 106 is a wonderful unit but it runs HOT watch the venting on the sides so it doesn¡¯t over heat. Now you just need a 191 and a 184.
Eric
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-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Stephen Sent: Thursday, March 18, 2021 11:29 AM To: [email protected]Subject: Re: [TekScopes] Type 106 On Thu, Mar 18, 2021 at 04:26 AM, Raymond Domp Frank wrote:
On Thu, Mar 18, 2021 at 04:07 PM, Dave Daniel wrote:
Look at the manual, page 1-4. It lists both > 12v and > 120v
depending on
the
termination (this does seem odd to me).
Nothing odd about that. It's (max) 12V into 50 Ohm, (max) 120V unloaded.
Many generators have an output impedance of 50 Ohm. Output voltage
halves when loaded by 50 Ohm, compared to open-ended. Faster ones are
spec'ed at 50 Ohm load.
The high-amplitude output of the PG506 reaches > 100V open-ended and
about 5 .. 6V into 50 Ohm, if I remember well.
The high-amplitude output of the PG506, and apparently, the Type 106,
may be used with Tek's tunnel diode pulser, as Eric describes.
Raymond
Thank you for the explanation.
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On Thu, Mar 18, 2021 at 04:26 PM, Raymond Domp Frank wrote:
Nothing odd about that. It's (max) 12V into 50 Ohm, (max) 120V unloaded.
Many generators have an output impedance of 50 Ohm. Output voltage halves when
loaded by 50 Ohm, compared to open-ended. Faster ones are spec'ed at 50 Ohm
load.
In this case, the loaded output is not (50/650)*120 V. The fast rise holds for the edge from negative to GND where the output tubes are cut-off. Only then the output impedance is 600R. The amplitude is determined by the current that the tubes can deliver. About 0.24 A. Gives 12 V in 50R. Albert
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Experience will teach you that 120V into 50 Ohm is unlikely, if even only for the reason I mentioned earlier (> 140W output) and that use as a high-amplitude generator is possible with lesser loads, as with the PG506's high-amplitude output.
FWIW, 10V is a common (damage) limit with 50 Ohm, so it's also a matter of taste.
Raymond
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On Thu, Mar 18, 2021 at 04:39 PM, Albert Otten wrote:
In this case, the loaded output is not (50/650)*120 V. The fast rise holds for
the edge from negative to GND where the output tubes are cut-off. Only then
the output impedance is 600R. The amplitude is determined by the current that
the tubes can deliver. About 0.24 A. Gives 12 V in 50R.
Thanks for that further explanation, Albert. The 240mA max is written on the front plate, with the 120V max. Raymond
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Just FYI: You don't *need* high-voltage to drive a tunnel diode (TD) of course. It's Tek's TD pulser that is dimensioned to be fed from a relatively high voltage. In it, relatively large resistors feed the TD, resulting in a nice current drive, where it's relatively easy to obtain a nice step voltage, with proper termination.
In one of my early TD pulsers, I used a 5 V power supply, generating a 1 MHz square wave. Only with some extra effort, a satisfactory step waveform (steep, sharp edge and flat top, as shown on a sampling system using a 25 ps S-4) could be achieved, rise time 170 - 180 ns. I used that pulser almost exclusively, until it was superseded by the even faster Leo Bodnar pulser (around 40 ps).
Remember, Albert? We spoke about that (and Jim Williams' pulser) years ago and I used your valuable advice to get there with my LV device.
Raymond
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On Thu, Mar 18, 2021 at 04:59 PM, Raymond Domp Frank wrote:
rise time 170 - 180 ns
Ahhh, that should be 170 - 180 ps, of course. Raymond
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On Thu, Mar 18, 2021 at 04:34 AM, Raymond Domp Frank wrote:
On Thu, Mar 18, 2021 at 03:06 PM, Eric wrote:
but good quality bnc is good to 4
Ghz
You do need very good BNC (cables, connectors, constant contact surfaces) to
get even close to that. Even good quality BNC tends to be visibly inferior
above 500 - 800 MHz. I'd rather leave GR874 on and use a converter plug to BNC
or a GRC-to-BNC cable when needed. OTOH, it's "only" a 12ns edge and with a
pulse generator, amplitude loss is less important than correct and constant
impedance all-through but even then I'd see no reason not to leave things as
they are and use a converter plug.
Raymond
I was actually thinking of leaving it alone, if not for the reflection issues, at least from a historical perspective. I¡¯d like to find good GR874 to BNC connectors, preferably in Europe
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On Thu, Mar 18, 2021 at 04:39 AM, Eric wrote:
The PG506 some times will not have enough drive current to trip the tunnel
diode in the pulser, It can be hit and miss especially with the ageing of the
pulser diodes I have not had any issues with the 106. But I also need to state
I have a sample size of 1. However my PG506 cant quite get the diode to trip
so I have to use the 106. The 106 is a wonderful unit but it runs HOT watch
the venting on the sides so it doesn¡¯t over heat. Now you just need a 191
and a 184.
I already have a 184, which I actually just recapped after it started acting very funny. (A little parentheses on this. It turns out both the 700uF and the 2000uF read 0 on the cap meter! The 700uF was even actually physically leaking stuff that, oddly enough, smelled very much like camphor or something, and was brownish sticky looking... out of the 2x47uF in parallel, one read zilch, and the other one read ok. Hummm.. Everything is good now. Maybe I should recap it entirely...) I also have a SG503. ¡°Maybe¡± I¡¯ll grab a 191 someday if I can find one at a decent and reasonable price.
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Now Raymond has me thinking I might need to check the rise time when I get back in to the lab tonight on mine make sure my BNC jack did not roll it off to far. I did the mod because the GR to BNC adaptors are getting harder and harder to find. Also 12ns rise time is only 29.166Mhz bandwidth so I should be fine there I expect but only testing will tell. On my 184 I have not had to recap yet but I am expecting it to play up any time now and will have to how much of a pain in the butt is that going to be?
Eric
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-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Stephen Sent: Thursday, March 18, 2021 12:12 PM To: [email protected]Subject: Re: [TekScopes] Type 106 On Thu, Mar 18, 2021 at 04:39 AM, Eric wrote:
The PG506 some times will not have enough drive current to trip the
tunnel diode in the pulser, It can be hit and miss especially with the
ageing of the pulser diodes I have not had any issues with the 106.
But I also need to state I have a sample size of 1. However my PG506
cant quite get the diode to trip so I have to use the 106. The 106 is
a wonderful unit but it runs HOT watch the venting on the sides so it
doesn¡¯t over heat. Now you just need a 191 and a 184.
I already have a 184, which I actually just recapped after it started acting very funny. (A little parentheses on this. It turns out both the 700uF and the 2000uF read 0 on the cap meter! The 700uF was even actually physically leaking stuff that, oddly enough, smelled very much like camphor or something, and was brownish sticky looking... out of the 2x47uF in parallel, one read zilch, and the other one read ok. Hummm.. Everything is good now. Maybe I should recap it entirely...) I also have a SG503. ¡°Maybe¡± I¡¯ll grab a 191 someday if I can find one at a decent and reasonable price.
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Raymond Domp Frank