¿ªÔÆÌåÓý

Date
Re: Advice on how to use an SA for test point troubleshooting
You may also use a differential probe, it is important to pay attention to the probe's input impedance and the common mode rejection ratio (CMRR) of the probe and oscilloscope. The input impedance of
By KB2LMN · #132747 ·
Re: Advice on how to use an SA for test point troubleshooting
One type of probe that could be used for this purpose is a passive probe with a bandwidth of at least 500 MHz and a maximum input voltage that exceeds +2 dBm. A passive probe is typically less
By KB2LMN · #132746 ·
Re: 5086-7337 *Yig Oscillator issue*
Yup, you got point :) I¡¯ll search a resistor to apply that method, ohm law at it¡¯s best. Regards, Ruben
By RubenRubio · #132745 ·
Re: Advice on how to use an SA for test point troubleshooting
Both SAs and Scopes measure voltage. If a signal level is CORRECTLY specified in dBm, the impedance must be 50 ohms unless otherwise stated. All that is necessary to do is the mathematical conversion
By Bruce · #132744 ·
Re: Advice on how to use an SA for test point troubleshooting
"Chuck Harris" <cfharris@...> writes: Ok, fair enough. I had assumed 2-3 dBm meant into a 50ohm load presented by whatever is downstream of this. If it's 2-3 dBm when you load it externally with
By Matt Huszagh · #132743 ·
Re: strange issue on Agilent 54641D MSO
Did this just start out of nowhere or were you testing something? Andrew
By KB2LMN · #132742 ·
Re: Advice on how to use an SA for test point troubleshooting
If the OP's description of the set point being 2-3 dBm, is accurate, you can do nothing else but use a 50 ohm probe to make the connection. dBm is totally undefined at the arbitrary high impedances of
By Chuck Harris · #132741 ·
Re: Hot air soldering tool
"Steve - Home" <sw.krull@...> writes: This is about $100 above your target, but I have the Quick 861DW and it's excellent. Matt
By Matt Huszagh · #132740 ·
Re: Hot air soldering tool
I got a GQ electronics 5200 hot air station for under $200 10 yrs ago...but ebay does not show any for sale now. That model has an iron output also. I've since gone to Metcal station for irons, so its
By John Griessen · #132739 ·
Re: Hot air soldering tool
I tried the cheap Sparkfun Hot-Air Rework Station - 303D and hated it. the temperature over and under shoots, build quality and safety (bad grounding) were all issues. It also has no auto shutdown in
By evan foss · #132738 ·
Hot air soldering tool
I¡¯m considering a hot air soldering tool and am looking for recommendations. I have a bench top Hart 200A with top and bottom heat to do larger parts but I¡¯m looking for a hand held unit for small
By Steve - Home · #132737 ·
Re: Advice on how to use an SA for test point troubleshooting
Matt - I agree - I was assuming a probe designed for Hi-Z and am unfamiliar with any others. Cheers! Bruce Quoting Matt Huszagh <huszaghmatt@...>:
By Bruce · #132736 ·
Re: strange issue on Agilent 54641D MSO
It also does it when I use the plastic-covered BNC of the original HP probe to "rattle" the BNC input. Wilko
By Wilko Bulte · #132735 ·
Re: 5086-7337 *Yig Oscillator issue*
QuotingRubin - You should not need to break the main coil circuit to measure the current - that may affect the stability of the circuit. Look at the main drive circuit. You will find a resistor
By Bruce · #132734 ·
Re: Advice on how to use an SA for test point troubleshooting
"Bruce" <bruce@...> writes: While a FET probe is nice, a suitable high-frequency passive probe (like the PML series) can absolutely work up to 500 MHz and beyond. In fact, you can make them
By Matt Huszagh · #132733 ·
Re: strange issue on Agilent 54641D MSO
Does it do that if you try moving the input with a non conductive tool? Or just your fingers? Andrew
By KB2LMN · #132732 ·
strange issue on Agilent 54641D MSO
I have an interesting phenomenon on my Agilent 54641D MSO. Upon cold powerup the trace of channel 1 is "all wiggly". The wiggliness is highly sensitive to mechanical movement of the BNC socket of
By Wilko Bulte · #132731 ·
Re: 5086-7337 *Yig Oscillator issue*
Ok, let¡¯s do a test set up for current measurements. My plan: separate the oscillator board and make jumpers between both with wire to open them and put the ammeter. Bruce - I¡¯m measuring rf
By RubenRubio · #132730 ·
Re: Advice on how to use an SA for test point troubleshooting
If you can find ont, I recommend attaching an HP FET probe to your SA. If you don't have one, it is a good idea to start looking for one. I find them a valuable resource for trouble shooting. Note:
By Bruce · #132729 ·
Re: 5086-7337 *Yig Oscillator issue*
Rubin - Two things to do: 1) Check ALL voltages to YIG sub assembly and check cable connections 2) Measure the YIG main coil current - you can ignore the FM coil - there will be a resistor used to
By Bruce · #132728 ·