If by "intensified beam" you mean the mode where the "selected" portion of the delaying sweep is brightened, then yes, there is. The problem is that I am only seeing the brightened part but not the rest of the sweep (unless I turn the intensity to dangerous levels, then I can see it very very faintly).
|
Re: Tektronix DM5010 NiCa 2.4V battery replacement
I have a couple control panels from a machine tool where the design was for the Varta 3.6V 70mAh batteries that were common on computer motherboards. When they became NLA, the company started using NiMh batteries without a redesign. They leak in under a year, and badly damage the interface board. I just received some rechargable Li-ion batteries to try, when I repair the boards.
12-pcs-LIR2032-Li-ion-Button-Coin-3-6V-Rechargeable-Cell-Battery-w-Tab-US-Stock/
Michael A. Terrell
toggle quoted message
Show quoted text
-----Original Message----- From: Harvey White <madyn@...>
Sent: Jul 21, 2018 7:02 PM
To: [email protected]
Subject: Re: [TekScopes] Tektronix DM5010 NiCa 2.4V battery replacement
On Sat, 21 Jul 2018 18:36:42 -0400 (GMT-04:00), you wrote:
You can still buy Ni-Cad replacements for cordless phones, but I always extend the leads and mount them away from anything they can damage. You may have to buy a three cell package and remove one cell, but some are easily reworked and cheap. They are sold by many places, and on Ebay. Agreed. There are two cell packages (somewhere) as well. The main
problem with the NiCds is twofold. One is the amount of time between
use/charge and loss of calibration data. The second one, (of more
interest once you finally have the calibration equipment) is the
damage a leaking NiCd will cause. Hopefully, the Lithium primary
cells don't do that. IIRC, such cells were not included in the
design, although I do remember one in the AWG series.
Harvey
|
Re: Tektronix DM5010 NiCa 2.4V battery replacement
On Sat, 21 Jul 2018 18:36:42 -0400 (GMT-04:00), you wrote: You can still buy Ni-Cad replacements for cordless phones, but I always extend the leads and mount them away from anything they can damage. You may have to buy a three cell package and remove one cell, but some are easily reworked and cheap. They are sold by many places, and on Ebay. Agreed. There are two cell packages (somewhere) as well. The main problem with the NiCds is twofold. One is the amount of time between use/charge and loss of calibration data. The second one, (of more interest once you finally have the calibration equipment) is the damage a leaking NiCd will cause. Hopefully, the Lithium primary cells don't do that. IIRC, such cells were not included in the design, although I do remember one in the AWG series. Harvey
Michael A. Terrell
-----Original Message-----
From: Harvey White <madyn@...>
Sent: Jul 21, 2018 3:13 PM
To: [email protected]
Subject: Re: [TekScopes] Tektronix DM5010 NiCa 2.4V battery replacement
On Sat, 21 Jul 2018 11:40:14 -0700, you wrote:
Hi everyone,
I need to replace the backup battery of a DM5010. It has leaked but I cleaned up the mess.
The service manual specifies a Nickel Cadnium 2.4V 150mAH at 14mA.
So far, I was able to find (on Mouser) a 2.4V 110mAH ().
Does it meet specification? In particular, we have 0.11AH vs 0.15AH.
I've absolutely no experience with rechargeable batteries. So I welcome your help. I'd suggest a different approach. The backup battery will leak again,
sooner or later. In addition, even with 150 mah, if it's in storage,
it will go below the point where the cal constants are valid. You
will have to provide various (highly accurate) voltages, including 250
or so and 700 VAC to calibrate this.
Calibration, unless you have the equipment, is a pain. (there are
ways of working around the accuracy requirement, but you still need
the 700 volts AC and 1000 volts DC).
I'd put in a lithium battery, I'd suggest a Tadiran TL-2155, which
will fit in the slot. You MUST put a diode in series to prevent the
battery from being charged, however.
Before you go to the trouble, I'd suggest temporarily wiring in two
small NiCd batteries, capacity not super important. Let them charge
up. Then go through and attempt to calibrate the unit as best you
can. What you're looking for is bad calibration constants, indicating
that the battery corrosion has damaged part of the backup circuitry.
At that point, if you can fix it, good, if not, then you'll have to
figure out a workaround.
One workaround is to rebuild/remake the CPU board with a more modern
processor, an AVR mega (a big one) would work. However, you'll want
to know how the insides interact with the processor, and I do not have
anywhere near complete information on that.
Given that information, a more modern board can be made, the functions
may be expanded, and you can restore the DMM to full service.
I put the battery in, and the memory storage was still not working, so
rebuilding is going to be what I do, for now, unless I find one that
is still working.
Harvey
|
On Sat, 21 Jul 2018 13:55:29 -0700, you wrote: Correction. I finally got my 7B92A to show both traces (delaying and delayed). I had the wrong combination of CRT intensity, B Horiz Intensity and 7B92A intensity/contrast settings. However what I am missing is the non-intensified portion of the delaying sweep. If I push some of the intensities to the max I can see it very, very faintly. This is obviously not working properly because at those settings I am certainly in the CRT-burning range of intensity. Any ideas? Thanks!!! Isn't there an intensified beam setting? I seem to remember one on the plugin. Harvey
|
Re: Tektronix DM5010 NiCa 2.4V battery replacement
You can still buy Ni-Cad replacements for cordless phones, but I always extend the leads and mount them away from anything they can damage. You may have to buy a three cell package and remove one cell, but some are easily reworked and cheap. They are sold by many places, and on Ebay.
Michael A. Terrell
toggle quoted message
Show quoted text
-----Original Message----- From: Harvey White <madyn@...>
Sent: Jul 21, 2018 3:13 PM
To: [email protected]
Subject: Re: [TekScopes] Tektronix DM5010 NiCa 2.4V battery replacement
On Sat, 21 Jul 2018 11:40:14 -0700, you wrote:
Hi everyone,
I need to replace the backup battery of a DM5010. It has leaked but I cleaned up the mess.
The service manual specifies a Nickel Cadnium 2.4V 150mAH at 14mA.
So far, I was able to find (on Mouser) a 2.4V 110mAH ().
Does it meet specification? In particular, we have 0.11AH vs 0.15AH.
I've absolutely no experience with rechargeable batteries. So I welcome your help. I'd suggest a different approach. The backup battery will leak again,
sooner or later. In addition, even with 150 mah, if it's in storage,
it will go below the point where the cal constants are valid. You
will have to provide various (highly accurate) voltages, including 250
or so and 700 VAC to calibrate this.
Calibration, unless you have the equipment, is a pain. (there are
ways of working around the accuracy requirement, but you still need
the 700 volts AC and 1000 volts DC).
I'd put in a lithium battery, I'd suggest a Tadiran TL-2155, which
will fit in the slot. You MUST put a diode in series to prevent the
battery from being charged, however.
Before you go to the trouble, I'd suggest temporarily wiring in two
small NiCd batteries, capacity not super important. Let them charge
up. Then go through and attempt to calibrate the unit as best you
can. What you're looking for is bad calibration constants, indicating
that the battery corrosion has damaged part of the backup circuitry.
At that point, if you can fix it, good, if not, then you'll have to
figure out a workaround.
One workaround is to rebuild/remake the CPU board with a more modern
processor, an AVR mega (a big one) would work. However, you'll want
to know how the insides interact with the processor, and I do not have
anywhere near complete information on that.
Given that information, a more modern board can be made, the functions
may be expanded, and you can restore the DMM to full service.
I put the battery in, and the memory storage was still not working, so
rebuilding is going to be what I do, for now, unless I find one that
is still working.
Harvey
|
Re: Tektronix DM5010 NiCa 2.4V battery replacement
On Sat, 21 Jul 2018 23:28:34 +0200, you wrote: Hi everyone,
My plan is only to fix this unit back to working condition, and hopefully
have fun in the process.
So there's no plan to re-make the CPU board, that's just to much work,
especially for a 4.5 digit only meter. Agreed, you don't have *three* of them and no TM5000 DMMS.
The DM5010 uses a "simple" trickle charger for the battery. However, the
charge current may seem too high.
Original battery specifcation is 150mA so trickle charge current should be
0.1 x capacity = 15mA.
However, the replacement battery specifies a trickle charge at 4mA, so I
may have to tweek the current limiting resistor.
Not necessarily so, has more to do with the "how long it's used and how long it's plugged in" vs. "how long the thing remains off." For normal use, I suspect there's not a problem with this, but when it's set on the shelf for two or three years, well, the CPU is toast.
I've noticed there is already a subject on eevblog regarding the battery
replacement.
May be I should move there (would be easier to post photos).
Or would guys prefer to continue here?
For my opinion, here is better. Photos could be put in the photo section. Harvey
Best regards,
On Sat, Jul 21, 2018 at 9:13 PM, Harvey White <madyn@...>
wrote:
On Sat, 21 Jul 2018 11:40:14 -0700, you wrote:
Hi everyone,
I need to replace the backup battery of a DM5010. It has leaked but I cleaned up the mess.
The service manual specifies a Nickel Cadnium 2.4V 150mAH at 14mA.
So far, I was able to find (on Mouser) a 2.4V 110mAH (
complete_11_Jan_25-21018.pdf).
Does it meet specification? In particular, we have 0.11AH vs 0.15AH.
I've absolutely no experience with rechargeable batteries. So I welcome your help.
I'd suggest a different approach. The backup battery will leak again,
sooner or later. In addition, even with 150 mah, if it's in storage,
it will go below the point where the cal constants are valid. You
will have to provide various (highly accurate) voltages, including 250
or so and 700 VAC to calibrate this.
Calibration, unless you have the equipment, is a pain. (there are
ways of working around the accuracy requirement, but you still need
the 700 volts AC and 1000 volts DC).
I'd put in a lithium battery, I'd suggest a Tadiran TL-2155, which
will fit in the slot. You MUST put a diode in series to prevent the
battery from being charged, however.
Before you go to the trouble, I'd suggest temporarily wiring in two
small NiCd batteries, capacity not super important. Let them charge
up. Then go through and attempt to calibrate the unit as best you
can. What you're looking for is bad calibration constants, indicating
that the battery corrosion has damaged part of the backup circuitry.
At that point, if you can fix it, good, if not, then you'll have to
figure out a workaround.
One workaround is to rebuild/remake the CPU board with a more modern
processor, an AVR mega (a big one) would work. However, you'll want
to know how the insides interact with the processor, and I do not have
anywhere near complete information on that.
Given that information, a more modern board can be made, the functions
may be expanded, and you can restore the DMM to full service.
I put the battery in, and the memory storage was still not working, so
rebuilding is going to be what I do, for now, unless I find one that
is still working.
Harvey
Best regards
|
Re: Tektronix DM5010 NiCa 2.4V battery replacement
On Sat, 21 Jul 2018 19:56:27 +0100, you wrote: On 21/07/18 19:40, anotherlin@... wrote:
Hi everyone,
I need to replace the backup battery of a DM5010. It has leaked but I cleaned up the mess.
The service manual specifies a Nickel Cadnium 2.4V 150mAH at 14mA.
So far, I was able to find (on Mouser) a 2.4V 110mAH ().
Does it meet specification? In particular, we have 0.11AH vs 0.15AH.
I've absolutely no experience with rechargeable batteries. So I welcome your help. One point to be aware of is how it is charged. If a cell is charged too fast or
for too long, it will be damaged. Quite true.
An "intelligent" charger will determine when a cell is fully charged, and stop
charging. Frequently a backup battery does not have an intelligent charger, but
simply "trickle charges" the cells all the time it is connected to the mains.
At that time of development, there was really no such thing as a smart charger, and it would have been about as complicated as the existing CPU board. All they did was to trickle charge it. The "use" senario was to have the unit plugged in and on most of the time, certainly enough (averaged over a week) to keep the battery charged when considering the power needed to keep the CMOS RAM alive. So you probably need to determine the trickle charging current in the circuit,
and compare that with the datasheet's spec. In the absence of more specific
information, it is usual to assume than trickle charging at "C/10" is OK, which
would be 11mA for a 110mAh cell. I think it was more like 1/20th C, but that's what I've remembered. All that was really needed was to put in more (use the 66% rule) than got taken out when the meter was turned off. Harvey
|
On Sat, 21 Jul 2018 13:09:29 -0700, you wrote: Hi, have you ever managed to fix the missing portions in the alt/intensified modes? My 7B92A never shows the alternate (delayed) sweep. It just shows the intensified portion of the delaying sweep. Any ideas? Thanks!! Possibly the first thing to think of is if it's in that mode at all? You might consider looking at the outputs of the switches (or where they show up) to see if they are proper. Switches can fail rather easily. Given that those outputs are correct, you need to look at connections and semiconductors next. Harvey
|
Re: Tektronix DM5010 NiCa 2.4V battery replacement
Hi everyone, My plan is only to fix this unit back to working condition, and hopefully have fun in the process. So there's no plan to re-make the CPU board, that's just to much work, especially for a 4.5 digit only meter. The DM5010 uses a "simple" trickle charger for the battery. However, the charge current may seem too high. Original battery specifcation is 150mA so trickle charge current should be 0.1 x capacity = 15mA. However, the replacement battery specifies a trickle charge at 4mA, so I may have to tweek the current limiting resistor. I've noticed there is already a subject on eevblog regarding the battery replacement. May be I should move there (would be easier to post photos). Or would guys prefer to continue here? Best regards, On Sat, Jul 21, 2018 at 9:13 PM, Harvey White <madyn@...> wrote: On Sat, 21 Jul 2018 11:40:14 -0700, you wrote:
Hi everyone,
I need to replace the backup battery of a DM5010. It has leaked but I cleaned up the mess.
The service manual specifies a Nickel Cadnium 2.4V 150mAH at 14mA.
So far, I was able to find (on Mouser) a 2.4V 110mAH (
complete_11_Jan_25-21018.pdf).
Does it meet specification? In particular, we have 0.11AH vs 0.15AH.
I've absolutely no experience with rechargeable batteries. So I welcome your help.
I'd suggest a different approach. The backup battery will leak again,
sooner or later. In addition, even with 150 mah, if it's in storage,
it will go below the point where the cal constants are valid. You
will have to provide various (highly accurate) voltages, including 250
or so and 700 VAC to calibrate this.
Calibration, unless you have the equipment, is a pain. (there are
ways of working around the accuracy requirement, but you still need
the 700 volts AC and 1000 volts DC).
I'd put in a lithium battery, I'd suggest a Tadiran TL-2155, which
will fit in the slot. You MUST put a diode in series to prevent the
battery from being charged, however.
Before you go to the trouble, I'd suggest temporarily wiring in two
small NiCd batteries, capacity not super important. Let them charge
up. Then go through and attempt to calibrate the unit as best you
can. What you're looking for is bad calibration constants, indicating
that the battery corrosion has damaged part of the backup circuitry.
At that point, if you can fix it, good, if not, then you'll have to
figure out a workaround.
One workaround is to rebuild/remake the CPU board with a more modern
processor, an AVR mega (a big one) would work. However, you'll want
to know how the insides interact with the processor, and I do not have
anywhere near complete information on that.
Given that information, a more modern board can be made, the functions
may be expanded, and you can restore the DMM to full service.
I put the battery in, and the memory storage was still not working, so
rebuilding is going to be what I do, for now, unless I find one that
is still working.
Harvey
Best regards
-- /* Lin Ke-Fong * anotherlin@... * I always do what I say, especially if it's something stupid. */
|
Re: OT: HP70843B 12 GHz BERT info needed
Here's my other post on hpagilent from before:
"I've been doing some searching on the part number of the output modules 5086-7956. Got some hits including apparently used in some version of the 8590 series SAs. I couldn't find anything like it so far in documents on these SAs though. Maybe it's just a wide-band (100 MHz-12 GHz) amplifier, used in other gear too."
I've been studying the output module more, trying to trace out the small board attached to it. I opened up the module too. The circuit is very tiny stuff on sapphire substrates. Looks like three identical GaAs amplifier or logic chips cascaded. I need to set up a microscope to see more detail.
Live voltage measurements on the interface from the big board to the small board/module were confusing because in operation, I think the whole amplifier is biased up and down to get the right DC out, while its input is AC coupled. Without knowing what conditions the instrument defaults to, it's hard to tell what it's telling the module. Opening it up will help to tell at least what's what in there and the basic signal path and structure.
Will post pictures and rough schematics if I figure out enough to make some sense.
Ed
|
Correction. I finally got my 7B92A to show both traces (delaying and delayed). I had the wrong combination of CRT intensity, B Horiz Intensity and 7B92A intensity/contrast settings. However what I am missing is the non-intensified portion of the delaying sweep. If I push some of the intensities to the max I can see it very, very faintly. This is obviously not working properly because at those settings I am certainly in the CRT-burning range of intensity. Any ideas? Thanks!!!
|
Re: OT: HP70843B 12 GHz BERT info needed
I'll try to post some pictures in the hpagilent group later. There are quite a few pieces in this complicated system, but I've gotten it somewhat figured out, structurally.
The 70843B is normally hooked to a 70004A or equivalent display MF via two local control cables (I forget the name - something HP specific control interface), and the 70004A needs a synthesizer (I forget the model) module installed, which supplies the clock (100 MHz - 12 GHz). The source unit in the 70843B amplifies and squares up its clock input with a GaAs amplifier, and sends it to the front panel in true and inverted forms via two of the output amplifier modules.
The clock internally also goes to a band-switched variable phase shifter system for skewing over a wide range. Since the system knows and controls the clock rate, the bands and amount of phase shift can probably be worked out precisely to desired time delay or whatever else is needed. The clock from the input amplifier goes through an HP8768K coaxial relay which routes it to a selected phase shifter module - a 6-12 GHz variable (with three varicap sections), a 3-6 GHz (similar), or a <3 GHz block with apparently PIN-switched delay lines of 250 pSec, 500 pSec, and 1 nSec, plus one varicap variable section. There is also a straight through mode that bypasses all the shifters. A second HP8768K selects the appropriate output and sends it to another GaAs amplifier, then that becomes the internal clock for data pattern generation.
The RX unit has the exact same kind of phase shifter assembly, but hooked up a little differently. The input amplifier clock outs are not used, just terminated, and its version of its delayed clock is used for decoding the data stream.
The TX and RX units each have a block full of small board sub-modules (about a dozen) that do the sub-rate multiplexing (TX) or de-multiplexing (RX). I have been able to ID some of the parts, which are mostly GaAs IC source-coupled logic drivers or switches, made by NTT, circa 1990s. I'll list them all here for reference, once I figure out all the types and quantities. These run at the top speeds involved, and apparently the rest of the stuff runs at one-quarter or one-eighth the clock rate.
I'll have more info later, and maybe some pictures too.
Ed
|
Hi, have you ever managed to fix the missing portions in the alt/intensified modes? My 7B92A never shows the alternate (delayed) sweep. It just shows the intensified portion of the delaying sweep. Any ideas? Thanks!!
|
Re: Tektronix DM5010 NiCa 2.4V battery replacement
On Sat, 21 Jul 2018 11:40:14 -0700, you wrote: Hi everyone,
I need to replace the backup battery of a DM5010. It has leaked but I cleaned up the mess.
The service manual specifies a Nickel Cadnium 2.4V 150mAH at 14mA.
So far, I was able to find (on Mouser) a 2.4V 110mAH ().
Does it meet specification? In particular, we have 0.11AH vs 0.15AH.
I've absolutely no experience with rechargeable batteries. So I welcome your help. I'd suggest a different approach. The backup battery will leak again, sooner or later. In addition, even with 150 mah, if it's in storage, it will go below the point where the cal constants are valid. You will have to provide various (highly accurate) voltages, including 250 or so and 700 VAC to calibrate this. Calibration, unless you have the equipment, is a pain. (there are ways of working around the accuracy requirement, but you still need the 700 volts AC and 1000 volts DC). I'd put in a lithium battery, I'd suggest a Tadiran TL-2155, which will fit in the slot. You MUST put a diode in series to prevent the battery from being charged, however. Before you go to the trouble, I'd suggest temporarily wiring in two small NiCd batteries, capacity not super important. Let them charge up. Then go through and attempt to calibrate the unit as best you can. What you're looking for is bad calibration constants, indicating that the battery corrosion has damaged part of the backup circuitry. At that point, if you can fix it, good, if not, then you'll have to figure out a workaround. One workaround is to rebuild/remake the CPU board with a more modern processor, an AVR mega (a big one) would work. However, you'll want to know how the insides interact with the processor, and I do not have anywhere near complete information on that. Given that information, a more modern board can be made, the functions may be expanded, and you can restore the DMM to full service. I put the battery in, and the memory storage was still not working, so rebuilding is going to be what I do, for now, unless I find one that is still working. Harvey
Best regards
|
Re: Tektronix DM5010 NiCa 2.4V battery replacement
On 21/07/18 19:40, anotherlin@... wrote: Hi everyone,
I need to replace the backup battery of a DM5010. It has leaked but I cleaned up the mess.
The service manual specifies a Nickel Cadnium 2.4V 150mAH at 14mA.
So far, I was able to find (on Mouser) a 2.4V 110mAH ().
Does it meet specification? In particular, we have 0.11AH vs 0.15AH.
I've absolutely no experience with rechargeable batteries. So I welcome your help. One point to be aware of is how it is charged. If a cell is charged too fast or for too long, it will be damaged. An "intelligent" charger will determine when a cell is fully charged, and stop charging. Frequently a backup battery does not have an intelligent charger, but simply "trickle charges" the cells all the time it is connected to the mains. So you probably need to determine the trickle charging current in the circuit, and compare that with the datasheet's spec. In the absence of more specific information, it is usual to assume than trickle charging at "C/10" is OK, which would be 11mA for a 110mAh cell.
|
Re: OT: HP70843B 12 GHz BERT info needed
Can you post some photo of the board somewhere on the internet? It is
always interesting see what is inside mysterious instruments
Il giorno sab 21 lug 2018 alle ore 20:20 Jim Ford <james.ford@...> ha
scritto:
toggle quoted message
Show quoted text
Hi, Ed.
I'm forwarding your message to another Ed I know who may know something
about this beast. I envy you for finding it!
Jim
------ Original Message ------
From: "Ed Breya via Groups.Io" <edbreya@...>
To: [email protected]
Sent: 7/21/2018 10:53:01 AM
Subject: [TekScopes] OT: HP70843B 12 GHz BERT info needed
I posted this in the hpagilent group a while back, but no one seems to
have info. That group seems pretty quiet lately, and I don't see
indications that it's moved to groups.io yet. Since it's mostly the
same folks in both groups, I thought I'd put it here for a bit where
there's more traffic, and hope for some more visibility. Sorry that
it's not Tek stuff, but it is highly related to fast pulse generators,
which are near and dear to our hearts.
Anyway, here goes - it may be fun and useful to talk (some more) about
fast pulsing technology, and GaAs devices, etc. I'd appreciate any info
on this unit or its guts.
"I just picked up this beast for cheap, figuring there would be some
fun microwave goodies inside. It seems to be a fairly obscure unit,
with no info on the guts, and barely any about the unit itself. I found
an operating and programming manual, and that's it. I've already parted
it out and found lots of interesting stuff, including the four main
source output modules, rated for tr and tf of about 30 pSec. These
should be good for fast pulse generator work, but not unless I can
figure out how to power them up and activate the control lines. The
outputs apparently can run up to 12 GHz (or Gb/sec) data rate, up to a
couple volts swing on 50 ohms. They appear to be some type of GaAs
amplifier, so could be complicated making the biasing all work out
right without any info or some reverse engineering of the support
circuitry.
Does anyone know of any technical info on the innards? This is from the
era of "No User Serviceable Parts Inside," and no manuals about the
insides.
My plan is to put some of the sections back together enough to trace
out the supply connections, and power up the pieces and see if I can
get some of the items operational. I realize it would have been cool to
use it in its complete form with lots of capability, but it would have
taken lots of effort and more stuff to cable it up to a 70004 display,
and maybe some SW, just to see if it worked. I'll be satisfied if I can
get the output modules figured out and working. There's also a bunch of
other microwave parts, and lots of EL-series "modern" high-speed ECL
parts all over the place.
The SMPS is big - over 400W out I'd say, and I plan to use the whole
carcass as a big multi-output supply after I figure out the modules and
such. It has heavy -5.2V and -2 V, handy for ECL work, besides the
usual +5V and +/-15V. There's room to add other supplies where the high
speed pulse guts were, and plenty of cooling - six 3" fans pull air
from one side, through the guts, and out the other side. Two are for
the PS, and the others for the working guts up front."
That's what I wrote before. I've been studying it more and have some
interesting observations that I'll report on later.
Ed
---
This email has been checked for viruses by AVG.
|
Tektronix DM5010 NiCa 2.4V battery replacement
Hi everyone,
I need to replace the backup battery of a DM5010. It has leaked but I cleaned up the mess.
The service manual specifies a Nickel Cadnium 2.4V 150mAH at 14mA.
So far, I was able to find (on Mouser) a 2.4V 110mAH ().
Does it meet specification? In particular, we have 0.11AH vs 0.15AH.
I've absolutely no experience with rechargeable batteries. So I welcome your help.
Best regards
|
Re: OT: HP70843B 12 GHz BERT info needed
Hi, Ed.
I'm forwarding your message to another Ed I know who may know something
about this beast. I envy you for finding it!
Jim
toggle quoted message
Show quoted text
------ Original Message ------ From: "Ed Breya via Groups.Io" <edbreya@...> To: [email protected]Sent: 7/21/2018 10:53:01 AM Subject: [TekScopes] OT: HP70843B 12 GHz BERT info needed I posted this in the hpagilent group a while back, but no one seems to
have info. That group seems pretty quiet lately, and I don't see
indications that it's moved to groups.io yet. Since it's mostly the
same folks in both groups, I thought I'd put it here for a bit where
there's more traffic, and hope for some more visibility. Sorry that
it's not Tek stuff, but it is highly related to fast pulse generators,
which are near and dear to our hearts.
Anyway, here goes - it may be fun and useful to talk (some more) about
fast pulsing technology, and GaAs devices, etc. I'd appreciate any info
on this unit or its guts.
"I just picked up this beast for cheap, figuring there would be some
fun microwave goodies inside. It seems to be a fairly obscure unit,
with no info on the guts, and barely any about the unit itself. I found
an operating and programming manual, and that's it. I've already parted
it out and found lots of interesting stuff, including the four main
source output modules, rated for tr and tf of about 30 pSec. These
should be good for fast pulse generator work, but not unless I can
figure out how to power them up and activate the control lines. The
outputs apparently can run up to 12 GHz (or Gb/sec) data rate, up to a
couple volts swing on 50 ohms. They appear to be some type of GaAs
amplifier, so could be complicated making the biasing all work out
right without any info or some reverse engineering of the support
circuitry.
Does anyone know of any technical info on the innards? This is from the
era of "No User Serviceable Parts Inside," and no manuals about the
insides.
My plan is to put some of the sections back together enough to trace
out the supply connections, and power up the pieces and see if I can
get some of the items operational. I realize it would have been cool to
use it in its complete form with lots of capability, but it would have
taken lots of effort and more stuff to cable it up to a 70004 display,
and maybe some SW, just to see if it worked. I'll be satisfied if I can
get the output modules figured out and working. There's also a bunch of
other microwave parts, and lots of EL-series "modern" high-speed ECL
parts all over the place.
The SMPS is big - over 400W out I'd say, and I plan to use the whole
carcass as a big multi-output supply after I figure out the modules and
such. It has heavy -5.2V and -2 V, handy for ECL work, besides the
usual +5V and +/-15V. There's room to add other supplies where the high
speed pulse guts were, and plenty of cooling - six 3" fans pull air
from one side, through the guts, and out the other side. Two are for
the PS, and the others for the working guts up front."
That's what I wrote before. I've been studying it more and have some
interesting observations that I'll report on later.
Ed
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Thanks, Dave!
I will try the largest value cap I have in parallel with C821 this
evening. The rest of the day is dedicated to my other addiction (I
meant strikethrough) hobby, playing musical instruments.
Jim
toggle quoted message
Show quoted text
------ Original Message ------ From: "Dave Hills" <dadhills@...> To: [email protected]Sent: 7/21/2018 9:44:06 AM Subject: Re: [TekScopes] Dead 7603
So I checked out the 8 V supply feeding the 5 V supply - it looks
really
bad! Similar waveform to the 5 V rail but dips from a high of maybe
14
V down to about 2 V. That's at the junction of the cathodes of
rectifiers CR820 and C821, C821, R821, and the collectors of Q829 and
Q835 on the Rectifier Board. If either of the rectifiers were shorted, you would see the waveform go
negative across C821. The minimum value of 2v indicates they are OK.
Then I checked at the anodes of CR820 and CR821; more convenient to
look
across C820. I saw about a 30 Vp-p near-sinewave there, with the
anode
of CR820 180 degrees out of phase with the anode of CR821.
This is OK.
I tried to measure C821 (18,000 uF) in-circuit with my cheapo Chinese
transistor/resistor/diode/capacitor checker, but it couldn't get a
reading. Ditto for C820 (0.1 uF, 100 V). I assume the transformer
effectively presents a short and throws off the checker.
This is what I would expect. Don't expect in-circuit measurements to
be meaningful with respect to a single component in a network. The
measuring instrument can't sort out a single component, as it see's
everything connected to it and makes a futile attempt to make sense of
the measurement.
Also, R821, from the cap/diode cathodes/transistor collectors point to
GND, reads 5.5k ohms, when it's supposed to be 4.7k +/-10%. I was
surprised to see it read high; most times the sneak paths make
resistors
read low in-circuit. Not that 5.5k probably makes a difference.
Either due to residual charge on C821, or R821 has drifted high, which
is not unusual if it is an aged carbon composition resistor.
Anyway, should I suspect the cap C821 or one of the diodes CR820 or
CR821? Or something else altogether?
All the info you have provided points to an open C821. Easy to confirm
by tacking an additional electrolytic cap across it and looking at the
waveform again. Even a small value, say, 100uF should make a
measurable difference. If the lowest level, 2v, increases, then you
have confirmed it is likely bad.
Dave
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OT: HP70843B 12 GHz BERT info needed
I posted this in the hpagilent group a while back, but no one seems to have info. That group seems pretty quiet lately, and I don't see indications that it's moved to groups.io yet. Since it's mostly the same folks in both groups, I thought I'd put it here for a bit where there's more traffic, and hope for some more visibility. Sorry that it's not Tek stuff, but it is highly related to fast pulse generators, which are near and dear to our hearts.
Anyway, here goes - it may be fun and useful to talk (some more) about fast pulsing technology, and GaAs devices, etc. I'd appreciate any info on this unit or its guts.
"I just picked up this beast for cheap, figuring there would be some fun microwave goodies inside. It seems to be a fairly obscure unit, with no info on the guts, and barely any about the unit itself. I found an operating and programming manual, and that's it. I've already parted it out and found lots of interesting stuff, including the four main source output modules, rated for tr and tf of about 30 pSec. These should be good for fast pulse generator work, but not unless I can figure out how to power them up and activate the control lines. The outputs apparently can run up to 12 GHz (or Gb/sec) data rate, up to a couple volts swing on 50 ohms. They appear to be some type of GaAs amplifier, so could be complicated making the biasing all work out right without any info or some reverse engineering of the support circuitry.
Does anyone know of any technical info on the innards? This is from the era of "No User Serviceable Parts Inside," and no manuals about the insides.
My plan is to put some of the sections back together enough to trace out the supply connections, and power up the pieces and see if I can get some of the items operational. I realize it would have been cool to use it in its complete form with lots of capability, but it would have taken lots of effort and more stuff to cable it up to a 70004 display, and maybe some SW, just to see if it worked. I'll be satisfied if I can get the output modules figured out and working. There's also a bunch of other microwave parts, and lots of EL-series "modern" high-speed ECL parts all over the place.
The SMPS is big - over 400W out I'd say, and I plan to use the whole carcass as a big multi-output supply after I figure out the modules and such. It has heavy -5.2V and -2 V, handy for ECL work, besides the usual +5V and +/-15V. There's room to add other supplies where the high speed pulse guts were, and plenty of cooling - six 3" fans pull air from one side, through the guts, and out the other side. Two are for the PS, and the others for the working guts up front."
That's what I wrote before. I've been studying it more and have some interesting observations that I'll report on later.
Ed
|
Tomas Alori
Michael A. Terrell