Telemakus FAQ
Please review the questions and answers below for Telemakus product support. If your answer isn't here or covered by the product data sheet, please submit a technical inquiry.
- I like the performance of the (TEA4000-7) attenuator. Can I get frequency operation extended down to 1MHz?
- Regarding the TEA4000-7 input power, the Max Input is stated as +23dBm. However, the P1dB is then specified at +30dBm. Which is correct?
- The TEA4000-7 data sheet mentions a USB HUB option. Is the HUB something Telemakus also sells?
- I am interested in the accuracy specs & frequency response (insertion loss vs. frequency & accuracy vs. frequency)of the TEA4000-7
- Does the TED6000-50 have a programming API available so that a custom application can gather data?
- Unable to activate the TED6000.
- Accuracy of the power meter is only +/-0.5dB. Is there something better?
- I’m trying to use the TED6000-50 on an older computer and get a message to update my system.
- I received my TED6000-50 power meter but there were no instructions with it.
- What is the input VSWR for the uMeter.
- The flash drive on my TED6000-50 seems to be damaged. Could it have been damaged by ESD?
- Is it possible to make a power meter that covers 5 MHz to 2 GHz, -40 dBm to +10 dBm for CATV applications?
- Can the TEG2700-6 Signal Generator (1800-2700 MHz) operate at 3-4 GHz or can it be modified to cover this?
- We’re using Agilent 83623’s as a 2.5 GHz source because it’s very clean. I’m not sure how ‘clean’ it needs to be for our application but how does your USB device compare (TEG2700-6)?
- Can Telemakus make a Signal Generator with frequency range of 1200-1700MHz?
- Extended or alternate frequency range generators.
- Can the TES3000-60 be controlled via USB by a "user" program?
- Power handling capability of the TES6000.
- What is the TES6000-30 insertion loss at 1GHz?
- Is it possible to control the TES6000-30 USB RF SWITCH with any programming language, for example LabVIEW?
- Can Telemakus make a Vector Modulator with frequency range of 1500-1700MHz?
- I’m having issues with the Visual Basic driver while running multiple devices. Can you help?
- Can I use the device driver with .dll file in MatLab and C#?
- Is there a way to use the Telemakus products with existing GPIB instruments?
- Problem running two attenuators with customer program.
- Do the Telemakus test products support Linux?
- Will the Telemakus API work with the Python programming language?
- Can you recommend a USB extender cable? Do you sell them?
- Do the Telemakus products have a “Certificate of Calibration”?
- Can I get a demo unit to try in my lab?
- Can you provide sample code, an API or SDK in .NET format
- Will the TEA4000-7 still work at frequencies greater than 4GHz
- Do you have Isolation and Insertion loss plots for the TES6000-30?
- With TES3000-60, do you know how much second harmonic is generated at different input levels?
Answer: Yes, most of the Telemakus devices can be tuned for varied or additional frequency coverage. There may be performance trade-offs and customer specific alterations require a minimum order of 4-5 units depending on the device. This eliminates NRE costs.
The TEA4000-7 tuned down to 1MHz is available as a standard part number TEA4000-7W
Answer: Regarding the power handling; the total power dissipation for the part is limited by maximum junction temperature and is therefore a function of average power. Distortion of RF signals is caused by the compression in the device and therefore is specified by P1dB and IIP3. If a high peak to average signal such as WCDMA is applied to the attenuator the maximum average power will be 23dBm but the peaks in the signal must also be kept below 30dBm to avoid compression.
Answer: Regarding USB Hubs. They are not all created equal. We have tested a few different models and not all work. We have tested one from Dynex with good results. If more ports are need, HUBs can be obtained with 16+ ports or HUBs can be cascaded. For example 2 of the Dynex 4 port HUBs would provide 7 ports when cascaded.
Our long term plan is to offer a HUB built into a small racking system with it's own power supply. Semi-custom test systems can then be configured for specific applications.
Answer: The TEA4000_7 includes a plot of Insertion Loss vs Frequency for the 0.0dB setting located on the flashdrive of the unit. You can access this by going to My Computer on your PC and double clicking on the drive named TEA4000_7.
Attenuation Accuracy is not a published specification for the unit but typically will be about +/-(0.2 + 2%) of the Attenuation value in dB. So the total insertion loss of the unit at 2.5GHz with a setting of 20dB could be estimated as:
Insertion Loss for 0.0dB @ 2.5GHz (from graph) + 20dB +/-(0.2 + 0.02*20)dB
Answer: As of April 2010, Telemakus devices will include the API library. An upgraded GUI is free for customers with older products. Contact support@telemakus.com with the Model Number and the Serial Number's for the units to be upgraded. The upgrade software will then be delivered via e-mail.
We recently purchased a TED6000 power meter from RFMW for assessment in a current project.
Although the device appears to have successfully installed itself on the computer, we are unable to activate it. There was no software or instructions with the device; we assumed it would operate automatically upon installation, but not so! Your data sheet suggests software is available from your website but no download is evident. Can you advise please?
Answer: Sorry to hear you are having difficulties installing with the TED6000.
From your e-mail, it sounds like the device correctly registered itself with Windows and all that remains is for you to load and activate the Graphical User Interface (GUI) software located on the device flash drive.
There should have been a blue instruction card packaged with the device describing the step-by-step operation on how to install the product. Page 1 describes how to attach the device to the PC. Page 2 (back page) describes how to load and run the GUI.
This information is also presented in a "readme.txt" file located on the product's flash drive and is copied below.
User Interface (GUI)
Software Installation
1) Complete the installation instructions for the device before installing the GUI
2) Open the My Computer folder on the PC and locate the device name under the Removable Storage Devices.
3) Open the device disk by double-clicking on its name or by using Windows Explorer
4) Locate the installation file named “Install <devicename>.msi” and double-click on that file to begin the installation process. The Installer program will take you through the remaining installation steps.
5) Start the program by clicking on the shortcut installed on the PC desktop or on the Start Menu
Problems: email – Support@Telemakus.com
+/- 0.5dB of accuracy is not much better than a spectrum analyzer. Since we have to tune up our transmitters for power, every 0.1dB is important.
Answer: The Telemakus devices will not replace a high end power meter costing 10x the price and they’re not meant to. If he’s interested in the highest accuracy, he needs to go with a more expensive, metrology grade product. FYI, he should probably be using metrology grade attenuators in his test set up as well. A typical 5W attenuator will have +/-0.5dB accuracy.
Feedback from an existing customer:
“I just talked to the guys at XXX on Thursday about the RMS detector and digital attenuator.
Both have worked great. They said the RMS detector was dead on with their expensive test equipment and liked the 0.25 dB steps of the digital attenuator.
They are looking forward to buying the signal source when it is available.”
Answer: Telemakus devices contain flash memory with the software used to drive them. The installer will check to see if Microsoft .NET 3.5 is installed on the PC, if not, the user will be directed to the Microsoft web page to download the FREE copy. Most newer PC's will all ready have this installed, older PC's will not (version 2.0 is typically found but no harm in upgrading)
I've attached a copy of the User software for the TED6000_50 Power Sensor
There is a Readme file that explains the normal installation process for the device. But, in this case, the customer will need to unzip the attached folder and double click on
"Install TED6000_50.msi"
The installer will check to see if Microsoft .NET 3.5 is installed on the PC, if not, the user will be directed to the Microsoft web page to download the FREE copy. Most newer PC's will all ready have this installed, older PC's will not (version 2.0 is typically found but no harm in upgrading)
The Readme file explains how to launch the software once it's been installed.
Answer: There should have been a blue instruction card packaged with the device describing the step-by-step operation on how to install the product. Page 1 describes how to attach the device to the PC. Page 2 (back page) describes how to load and run the GUI.
This information is also presented in a "readme.txt" file located on the product's flash drive so once you plug in the device, you can access the readme.txt file.
Answer: The nominal return loss is 20dB or VSWR of 1.2:1.
Answer: After calibration, Telemakus products are packaged in protective, anti-static bags and placed in padded, anti-static boxes for shipping. They are stored in the warehouse at RFMW until shipped to a customer order.
RFMW does not remove the devices from their protective bags/boxes unless physical damage to the box is detected at incoming inspection. If the contents require inspection, the receiving and shipping areas at RFMW are static controlled environments with conductive waxed floors and trained personell wearing ESD smocks and conductive wrist and shoe straps. And outwardly damaged devices would be returned to the manufacturer.
Note that Telemakus has performed extensive and abusive tests on their products (such as unplugging in the middle of operations etc.) and haven't been able to force a failure yet.
RESOLUTION - Thank you for the help. The problem was that I didn't rename the volume properly when formatting it. But everything seems to be working in order now.
Answer: After a quick review of available detectors it looks like 5MHZ to 2GHz is possible but would not be RMS and so accuracy would be lower. This would require a new design as the existing TED6000-50 can not be modified to work below 50MHz. Depending on the quantity required; we could make this a standard product
Answer: 3 - 4 GHz is within the range of the existing design. Telemakus would have to look at power output and change the harmonic filtering. This would be a customer specific design and require a min order of 4-5 pieces
Answer:
Spurs: The TEG2700_6 beats the 83623 hands down at 2.5GHz (-80dBc vs -60dBc).
Phase Noise: The two are comparable for Phase Noise at 10kHz and 100kHz offset, with the 83623 being better below 10kHz offset (it uses a more stable reference)
Harmonics: The 83623 wins here (-20dB compared to -30dB for the 2nd Harmonic) We can do a special that would trade a few dB Ouput Power to be <-30dB
Freqency Step Resolution: Both units are 1kHz (unless you have the 1Hz 83623B model with option for high resolution)
Pricing: The TEG2700_6 is about 10x less expensive than a used 83623. (Agilent can't touch this for Price/Performance)
Answer: Yes, 1200-1700MHz is within the range. Performance would be similar to TEG2700 with typical output power of 8dBm but 2nd harmonics would be about -10dB due to the internal filtering. An external filter can be used by the customer if harmonics present a problem. Part number will be TEG1700-C. Customer specific alterations require a minimum order quantity depending on the device. This eliminates NRE costs.
I was wondering if Telemakus can provide synthesizers which operate in slightly different frequencies than the TEG2700-6 operates (1.8-2.7GHz). I am looking into other synthesizers that can go up to 2.9GHz. Can the TEG2700 be operated out of the box up to 2.9GHz with some performance degradation? Alternatively can Telemakus provide another synthesizer (maybe custom) that will work up to roughly 3GHz?
Answer: The on-board firmware will preclude use of the TEG2700 above 2.7GHz. However, with firmware and component modifications, the basic Telemakus generators can be extended up to 3GHz.
The output power will degrade slightly, and harmonics will be an issue as 2x 1.8GHz, 3.6GHz will be that much closer to 3GHz limiting the filtering designed into the product. If we were to also raise the lower frequency, 1.8GHz, to approx 2.2GHz this would allow us more flexibility.
Eg: do you publish the protocol for controlling the switch so that I can control it from my application on a PC? (I don't want to use your "graphic interface")
Answer: Telemakus products can be controlled from PC programs using .NET compatible drivers. Sample programs are available from Telemakus LLC.
We are looking for a solution whereby we can switch the RF output from a modem to one of two antennas and we wish to control the RF switch via a USB port.
The TES6000 looks like an ideal solution however i have some concerns regarding the input power. The modem can output up to 2W (33dBm) in the GSM band and the max. input specified for the TES3000 is 23dBm(0.25W). However the TES6000 datasheet shows a continuous wave power of 33dBm is allowable. With power levels in mind would the TES6000 be suitable for our application?
Answer: Thank you for your inquiry.
You are right, the TES3000-60 has a max power of 23dBm due to the termination internal to the device. The TES6000-30 has a P1dB of 33dBm but has no internal termination and is therefore reflective. The real limit is power dissipation in the switch which is limited to 0.8W. If you are using a pulsed modem with a peak power of 2W then the loss of 1dB at 900MHz will create a dissipation of 0.2W and will therefore be well within the limit.
The switch will dissipate more power during switching. Ideally you should switch when the RF is OFF.
Answer: Specified insertion loss is 2.0dB max. However, at 1GHz, typical insertion loss is approximately 0.85dB.
Answer: Yes
Answer: No, The vector modulators being used internally are band specific and will not work outside the specified frequency.
Answer: It seems that Windows has many surprises when using multiple devices on a single PC. The inter-process messaging took longer to work out than we originally thought but here it is.
The driver file (TEA4000_W_drv.dll) works well when it is used correctly but the error handling routines still have some bugs. In particular, if you attempt to access a unit using a Serial Number that does not exist, Windows will throw an exception error. We are trying to understand this problem. It has to do with the method that Windows disposes of unused objects during the closing process. That issue should not be a problem for you if you always reference Serial Numbers that are actually attached to the PC.
A demonstration program is included in this version to show how to interface with the TEA4000_W_drv.dll. The program is called TEA4000_W_demo. It is included as a Visual Studio 2008 project so it includes all of the VB source files for the demo project. The primary VB source code will be found in C:\Program Files\Telemakus LLC\TEA4000_W Attenuator\TEA4000_W Driver Demo\Form1.vb
If you would like to work with the project in Visual Studio, you can launch VS then load the TEA4000_W_demo.vbproj file. You will then need to show Visual Studio where to locate TEA4000_W_drv.dll by adding a reference to it.
There are only 4 methods (functions) in the TEA4000_W_drv.dll that are listed below:
Public Function Launch_Main(ByVal mySN As String) As Boolean
This function loads the driver library and opens a USB communication path to the target Serial Number device. The function assigns the Serial Number to the driver object created so that the Serial Number is no longer required to reference the object. The Serial Number argument (mySN) is the 4 digit string from the device Serial Number.
Public Function Set_Atten(ByVal Atten_dB As Double) As Boolean
This function sets the attenuation value of the referenced device. The valid range of Atten_dB for the TEA4000_W is 0 - 31.75dB in increments of 0.25dB. Values outside this range are rounded to the nearest valid 0.25dB increment. The RF attenuation of the physical device will also include it's Insertion Loss at the 0dB setting. This additional Insertion Loss must be accounted for by the user in applications requiring precise setting of RF power.
Public Function Close_Main() As Boolean
This function releases the USB handles to the controlled device, and closes the inter-process messaging routines to the driver object. It does not dispose of the driver object. The Unload_DrvLib() function must be called to complete the closing process.
Public Function Unload_DrvLib() As Boolean
This function completes the closing process by signaling the driver object to cleanup any pending transactions and prepare to be unloaded. The driver object then signals Windows that it is ready for disposing and Windows completes the cleanup.
This information is also included in the attached ReadMe.txt file.
To Install the new software:
1) Unzip the Upgrade Package folder
2) Locate and double-click the " Install TEA4000_W.msi " file. There is no need to un-install the previous version. The new installer will remove it for you.
3) If you would like to keep the files located on your TEA4000_W devices updated, you can copy these upgrade files directly to the TEA4000_W flashdrives but this process is not required for the device to work.
RESOLUTION: This concern involved issues with early versions of the API's where Windows did not correctly recognize multiple devices of the same type attached at the same time. The problem has been corrected in the latest release of the API libraries for all Telemakus products. Customers reporting any problems like these should contact Telemakus support for a free API upgrade which will be delivered by e-mail.
Thank you for driver , I am in vacation now so I will try the driver only next week.
I can you use with dll file in Matlab and C#?
Answer: To my understanding, Visual Basic.Net is compiled to Microsoft Intermediate Language and therefore, should be compatible with C# (which is also compiled to IL). However, the TEA4000_W_drv.dll has not been tested this way.
I am less certain of compatiblity with Matlab. You will be the first to interface our products to Matlab. I think Matlab is written in C++ which allows the use of unmanaged code. Not all Matlab code would be unmanaged code but the code that is unmanaged code would be difficult to interface to TEA4000_W_drv.dll without Windows complaining.
“H“How do we control our existing gear via USB, which has old GPIBs. What I am looking for is a device which plugs into the old GPIB, but converts immediately into USB, so we could avoid the huge GPIB cables and the GPIB interface cards in the PC. The Labview guys have something, but I need to study it better.”
Answer: National Instrument, Agilent and a couple of others sell them for about $500.
We use one to interface to older instruments such as the Agilent 82357A/B.r />
It's amazing that one can purchase 2 of our newer instruments for nearly the same price as it takes to talk to one of the older ones.
I have problem to use with your digital attenuator in our system.
With your program I can control on 2 different attenuator, but when I try to use with your dll in my code I can control only 1 attenuator.
I attached two simple code in VB, first need to control on attenuator SN:0002 and the second need to control on attenuator SN:0004.
When I run this program I can only control in attenuator SN:0002.
Please help to understand what is the problem.
Answer: I took a quick look at the code you sent. What I can see is the difference between the code for driving SN:0002 and SN:0004.
The difference is that the code for SN:0002 correctly closes the USB channel to the part and then correctly unloads the driver before ending. This is done with the statements:
myAtten1.Close_Main()
myAtten1.Unload_DrvLib()
The code for SN:0004 does not include these statements and therefore the device will operate correctly the first time the program is run. But, when the program is run a second time, the SN:0004 device will still be linked to the old channel and driver process that was not properly closed. The second program can not operate until the SN:0004 device is free. This is the same problem created with all .NET objects that are not properly released before ending the application program.
To free the SN:0004 you may need to do two things. First, open the Application Manager in Windows and close any driver processes that may still be open. (You can also close these by rebooting the computer) Second, you may need to unplug the SN:0004 device from the PC and plug it in again to reset the device.
If you the free the SN:0004 device and add the Close_Main() and Unload_DrvLib() lines to the SN:0004 program, I think everything will work fine for you.
RESOLUTION: This concern involved issues with early versions of the API's where Windows did not correctly recognize multiple devices of the same type attached at the same time. The problem has been corrected in the latest release of the API libraries for all Telemakus products. Customers reporting any problems like these should contact Telemakus support for a free API upgrade which will be delivered by e-mail.
Answer: Telemakus only supports Windows XP and Vista right now.
Answer: Yes. The product comes with the .dll library file and source code for an example calling program as well as our standard GUI so the product can be used manually immediately out of the box with no code writing required. The Visual Basic.NET source file for the demo program should contain the C header file to access our .dll functions with Python. The library is COM visible, so as soon as you show Python where to locate it (in the Program installation folder) you should be able to access the methods in it. The API methods can be called from C++, C# and Visual Basic.NET
Answer: RFMW doesn’t normally provide non-RF related products. That may change as this product becomes more popular and customer requests for accessories increase. For now, Telemakus recommends USB cables from Microbarn as they have personal experience with them. However, they have noticed that some cables fit tighter than others. It appears that the more expensive cables have a more positive feel when attaching a device.
An accessory “kit” may be offered in the future that might include a USB cable, hub and adaptors as well as RF cables and SMA-N type adaptors and attenuators. We’ve already looked at a pouch that would accept a Telemakus device and be large enough to hold additional accessories.
A customer running a certified lab with ISO/IEC 17025:2005 wants to know if the Telemakus power meter comes with a “certificate of calibration”. If so, he would like to see a copy of the cert to see if he can use the power meter in his lab.
Answer: At the present time, Telemakus does not supply a certificate of calibration with the unit and do not make any claims to follow any particular international metrological standards (all of these things add cost).
They are however, calibrating the unit against other equipment that is calibrated and maintained following those standards. This may qualify Telemakus to eventually claim to be a lower tier calibration facility that can issue such certifications but at the present time, on paper, they do not have authority to do so.
Most ISO companies allow the use of "uncalibrated" equipment (eg. power supplies) provided that the equipment is used with other calibrated equipment or calibrated following an internally written process that demonstrates the device meets its published specs.
There are some advantages to being able to produce "Pedigree" paperwork for the device. And Telemakus might offer a certifcation in the future as an add-on cost (by using an outside certified calibration lab). But the specification of +/- 0.5dB accuracy would preclude use of the device in most high accuracy applications demanding tight tolerances anyway. These are some of the tradeoffs between a $300 vs a $3000 device.
Answer: The biggest concern with sampling test equipment is the physical condition upon its return. With low cost test equipment such as Telemakus, the best way to get a sample is to provide a purchase order or credit card number with a contingency. For example, you might arrange with the distributor for a 15 day “trial”. If you like the device, you keep it and pay the invoice or allow your card to be charged. If not, you can return it for a restocking fee that will cover the cost of retest/recertifying performance.
Note that retest/recertification and restocking is an average cost of ~$50 but varies depending on the device. If the housing is damaged or cracked, then retest/recertification could be as much as the cost of a new unit.
Answer: Yes, available upon request.
Answer: Yes, the TEA4000-7 is meaured to 4GHz but can be used up to 6GHz with reduced performance. Insertion loss, attenuation accuracy and return loss all degrade and are not tested above 4GHz. For operation up to 8GHz, we recommend the TEA8000-6
Answer: Yes, the TES6000-30 Isolation plot can be viewed HERE. The TES6000-30 Insertion Loss plot can be viewed HERE.
Answer: We do not collect data on the second harmonic performance of these devices so there are no graphs or charts. However, it is possible to estimate the Second Harmonic value using the Output Second Order Intercept point for the device.
The Output Second Order Intercept point (OSOI also called IP2) for this device is not given on the Telemakus datasheet but is estimated to be +80dBm.
The formula that allows you to predict the Second Harmonic (SH) level in dBc (dB below the carrier) as a function of the output power (Pout) at the fundamental frequency is then given as:
SHdBc =
OSOIdBm -
Pout,fund,dBm
where: Pout,fund,dBm is the desired output power at the fundamental frequency in dBm
Example:
If my desired output power is +10dBm at 1000MHz then for the TES3000_60 with IP2 of +80dBm, the estimated Second Harmonic level would be
SHdBc = +80dBm - (+10dBm) = 70dBc or 70dB below the fundamental or -60dBm at 2000MHz.
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