Question about Square Electronics - Others

1 Answer

My Hameg 203-6 scope i think may have a problem.

In that on channel 1 when i invert the square wave 2v cal signal the invert flips the whole signal down aprox only half the graticule i.e. not inverting in the one position but is still showing correct voltage of 2v when you move the trace back up to a line. But on channel 2 the inverted wave inverts on lines with the graticule. Is this the norm or does this need adjustment. The DC Balance adjustment checked is correct on both channels. I have a schematic for the scope if i need to make an adjustment. Regards.

Posted by on


1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points


    An expert that got 10 achievements.


    An expert that got 5 achievements.


    An expert who has written 50 answers of more than 400 characters.

  • Expert
  • 193 Answers

You may have channel 1 set to DC input and channel 2 set to AC. If your DC balance is set correctly, as you mentioned, then there is a DC component to the waveform. Having the scope set to DC will show this DC offset, but set to AC, it will not be seen.

Posted on Dec 02, 2017

Testimonial: "Thank you Clint; i may have done this..i will try again later and see if this was the case. Regards."


4 Suggested Answers

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya Technician can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US.
click here to Talk to a Technician (only for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

  • 68 Answers

SOURCE: Trace inverter high AC voltage

Not to worry. First thing is you are probably not using a true RMS volt meter. You are reading an average voltage of peak. You have a sine wave inverter. The RV 2012 has a peak of 164 volts. I could go into much more tech detail but may confuse you. If you want to learn more her is a link from my dealer tech sheets. Also if you have checked voltage in a float state it will read high.
Hope this helps you
Thank you for using Fixya and please rate us.

Posted on Mar 26, 2009

  • 290 Answers

SOURCE: I would like to run my Canon i550 printer with a

pure sine wave will be the best option ,but note it is not very possible to get a pure sine wave type

Posted on Feb 25, 2010

  • 1 Answer

SOURCE: Trace / Xantrex SW5548 inverter (one of two in a

Because it's made in CHINA!!!!

Posted on Jul 09, 2011

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

I have a 1990 olds 98 regency. When u go around curves to the left it dies. Now it wont start at all. Its not the fuel,is it coil pack or in steering column

Please check for spark, injector pulse and test Crank position sensor.
1. Use a lab scope to check the square wave signals from the crankshaft sensor at the module pins G Dark Blue/White and H Light Blue/White.

2. Should produce roughly a 0-5 volt square wave. Voltage could be a little higher, depending on the brand of module.

3. If there is no signal on one of the wires, then check the wire for an open or short to ground.

4. Disconnect the crank sensor and check for power and ground to the sensor on the White/Black and Gray/Red wires.

5. Check the connections at the ignition module for being clean and tight.

6. Verify that the Pink wire at pin P is 12 volts key on and cranking. Verify the ground on pin K Black/White wire.

Mar 26, 2015 | Cars & Trucks

1 Answer

1999 mazda millennia wont start showed p1345 code is there a way of testing the camshaft position sensor

you can test the cam shaft sensor ,but you will need a lab scope.
depending on what type of sensor if its a 2 wire sensor it will produce a a/c signal, if it a 3 wire sensor it will produce a square wave signal. but with out a lab scope. it just a guess

Sep 22, 2013 | 2001 Mazda Millenia

1 Answer

Where can I get PCB for my xantrex DR Series power inverter. PCB number is 39cx3yM. I'm in Tanzania.

Officially Xantrex has the position of Note: In order to protect our intellectual property, Xantrex does not release schematics, part lists or wiring diagrams to the public. Xantrex does not sell internal parts to the public. If you need an internal part replaced, your inverter will need to be serviced by an Authorized Service Center or at the Xantrex factory.

So your options are to ship it to an authorized Xantrex repair depot, or reapair it based on electrical knowledge in general

If you decide the latter approach, you have to see if there are any IC's or other semiconductors you can identify. If they are true sine wave inverters- the wave form genesis is what counts- you will have to locate the low frequency oscillator, if it will power up and you have an oscilliscope. you can see if the waveform genesis is a square wave originally, triangle wave or a sine wave. essentially move through the traces to see where the signal goes away. your failure point will be close.

If the original waveform is sine wave, applying class A, AB or B audio amplifier principles should allow you to effect repair.

If the original waveform was square wave or triangle wave- the wave form is shaped by an LC network. Depending on what sized Capacitors and inductors are inside of the cabinet will determine where the sinewave form was achieved. If they are physically small, the waveform was shaped off the Pulse Width modulation circuit, audio amplifier principles should apply in the circuit trace and troubleshooting with the scope.

if they are physically large- the waveform is shaped at the output device(s) Usually an IGBT or power darlington..

If you are working with a modified sine wave inverter, the principles and block diagram is similar to a Class D audio amplifier or a crude AM transmitter with none of the pass filters (oversimplification perhaps)

this ought to be either enough of a start or enough of an outline for you to determine how you want to proceed.

Dec 30, 2011 | Electronics - Others

1 Answer

How to set swr galaxy dx 949

you do not "set" cannot set it on the radio. the radio can tell you what yourswr is. it can take an swr measurement. swr has to do with the antenna system. in order for the radio waves to radiate from the antenna properly, the physical length of the antenna must match the length of the radio waves. if the antenna is too long or too short you will have a higher swr ratio. the higher the ratio the less energy will leave the antenna. but that energy needs to go somewhere, so it goes back into the radio which causes damage and can ruin a radio.

first turn the channel to 20. then switch the meter switch to CAL. then key the radio. while keyed, turn the CAL knob up until the needle in the meter gets right to the CAL Mark. next flip the meter switch and key the radio. where ever he needle is, is what your swr is.if it is more the 1.5 that's getting high. if its over 2 you are in the danger zone. if its over 3 you are damaging your radio. you must repeat the calibration proceedure for every figure out weather your antenna is too long or short, you compare the swr readings from channel 1 and ch 40. if the swr is higher in 1 then on 40 the entenna is too short. if its higher on 40 then 1 its to long.

Aug 05, 2011 | Galaxy Radios DX-949 40-Channels Base CB...

1 Answer

29 LTD CB Radio: Calibrate cb radio...

The CAL is to calibrate meter for reading SWR (standing wave ratio) which is reflected power when transmitting back to receiver(radio) from antenna system.
This CAL switch position when selected and mic keyed uses the CAL knob to align the meter needle with inverted red triangle next to cal on meter. Then when you select SWR switch position meter will display accurately when mic is keyed for that channel. Now notice the difference when you go between channels 1 and 40. The ant led light will act as idiot light if it is not lit then you are most likely safe to transmit.
I say system because your vehicle, antenna and coaxial cable are all part of this system. When you have a high reading and have to trim you antenna this is really calibrating the antenna to the vehicles body which acts as a ground plane.

May 16, 2010 | Cobra 29 LTD CB Radio

1 Answer

How to set SWR readings to my K40 Antenna without a meter

If you have a cobra 29 then you have a meter. There is no way to Tune an antenna without a meter. You need a device that can read the reflect, or Standing Wave Ratio.That is a standing wave of RF energy that instead of leaving the antenna, is going back down the feed line to the radio and in time hurting the radio.

If you have a cobra 29 LTD, it has a build in SWR meter. It is not as accurate as an in line meter, but it will get it close enough not to hurt the radio. Here is how to do it.

Turn on the radio, with the antenna hooked up. Never key with out an antenna hooked up.

Set the switch all the way to the left(S/RF SWR CAL) to CAL. this stands for calibrate.

You will notice there is a knob right next to the channel selector knob marked SWR CAL as well. Start with the knob turned all the way to the left.

Put the radio on Channel 20. This is just about the middle of the band.

Key the radio and hold it. While holding the key on the mic, turn the SWR CAL knob up until the needle on the meter hits the mark "CAL". there is a triangle, and a gap in the line. The needle needs to be at the point of the triangle in the gap.

NOW, while still holding the mic key, flip the switch from CAL to SWR. You should see the needle immediately swing back. What ever the needle is on at this point is your SWR reading. use the set of numbers on the top of the meter, that's for SWR measurement.

If the needle does not swing back, and is in the rad, the antenna is WAY off. There are some reference points on the scale. The first gap in the line is 1.5 SWR. if the needle is there or less that is fine. then you have 2 and 3. 2 is not so great, but not extremely bad, but you should try to get it lower. 3 is really bad. Anything past 3 is considered infinity, and is really really bad.

If its high, then your antenna is either too long or too short. So how do you know which?

Here is how.

Turn to channel one and repeat the SWR process from above. Make note of the reading.

Then turn it to channel 40. Repeat the process again and take note of the reading.

Now, if the SWR is higher on channel 40 then 1, then your antenna is too long and you must shorten it. If the reading is higher on 1 then 40, then your antenna is too short, and you must lengthen it.

Make adjustments in length about an 1/8th inch at a time until you have either the same reading on 1 and 40 or real close, and or the reading on channel 20 is really low.

If you get it so that the reading on 1 and 40 are the same, then the SWR reading on 20 will most likely be almost nothing, unless there is either something wrong with the antenna, coax, or its just a crappy antenna.

K40 should be able to get a nice low SWR.

Apr 04, 2010 | Cobra 29 LTD CB Radio

2 Answers

Tunning the antenna on radio shack cb trc-447

After installing the antenna, follow these steps to adjust the
standing wave ratio(SWR).
1. Turn on the CB.
2. Set S/RF/SWR/CAL to CAL.
3. Key the Mic and rotate SWR CAL so the meter points
to CAL.
4. Unkey Mic.
5. Set S/RF/SWR/CAL to SWR.
6. Key Mic again and note the actual measurement on
the SWR scale. Refer to the following table to interpret
the reading.

1:1 - 1.5 Great
1.5 - 2:1 OK
2:1 - 3:1 Not So Good
Higher than 3.1:1 Terrible

The ideal standing wave ratio (SWR) is 1:1, or a meter
reading of 1 on the SWR meter's top scale. A SWR ratio
of 1.5:1 to 2:1 is excellent for most mobile CB antenna

Check the SWR on Channel 1 and Channel 40
If the SWR is higher on 1, make the antenna longer
If the SWR is higher on 40, make the antenna shorter
Most antenna's are adjustable. Make small adjustments at a time.

Oct 10, 2009 | Radio Shack TRC-447 CB Radio

2 Answers

I got a output voltage of 100.1 on a trace dr3624

The rms voltage is what counts, because it tells how much power the output will deliver to a resistive load. Inexpensive multimeters on their AC ranges are usually average-responding rms-calibrated meters. This means they measure the average of the absolute value of the AC component of the signal, and display that average multiplied by about 1.11 (actually, pi over sqrt(8)), the ratio of rms to average value for a pure sine wave. That way, the meter will give the right rms reading for a sine wave.

If the signal is a square wave, where the average and rms values are equal, the average-responding meter will read 11% too high.

Many inverters put out a modified sine wave (MSW), which sits at zero for a while, goes to a constant positive level for a while, goes back to zero for a while, and goes to a constant negative level for a while to complete the cycle. The positive and negative parts of the signal have the same magnitude and duration.

The rms and average values of an MSW depend on its duty cycle D, the fraction of a cycle for which the signal is not at zero. In a well-designed inverter, the duty cycle will be adjusted when the DC input voltage goes up and down to maintain the nominal rms output voltage. If we use peak voltage Vp to mean the magnitude of the positive and negative voltages the signal goes to, then Vavg for an MSW is equal to Vp times D, and Vrms is equal to Vp times the square root of D.

The duty cycle for which an MSW will have the same rms to average ratio as a sine wave is 8 over pi squared, or 81%. For any duty cycle less than this, an average-responding meter will read a lower voltage than the inverter rms output, and for a duty cycle higher than this, the meter will read too high.

If your MSW inverter is putting out 120 volts rms and its duty cycle varies from 50% to 75%, the meter reading will vary from 94 volts to 115 volts. I avoid the problem by using a Radio Shack 22-174B true rms digital multimeter.

Aug 27, 2009 | Xantrex Technology DR2412 Inverter /...

Not finding what you are looking for?
Electronics - Others Logo

Related Topics:

84 people viewed this question

Ask a Question

Usually answered in minutes!

Top Square Electronics - Others Experts

Donald DCruz
Donald DCruz

Level 3 Expert

17130 Answers


Level 3 Expert

102366 Answers

Brad Brown

Level 3 Expert

16404 Answers

Are you a Square Electronics - Other Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides