Hello,
I have a few offical Nordic Dev Kits available if anyone would like them. 2 nRF24L01P kits with RF modules and main boards and a few nRF51-DKs. I am in the Pasadena, CA area near JPL. If anyone would like to meet to do a hand off let me know.
@Nca78 I suggest downloading the "command line tools" as well.
https://www.nordicsemi.com/Software-and-tools/Development-Tools/nRF-Command-Line-Tools.
@Nca78 nRFgo Studio has been put to sleep. nRFgo studio does not have support for the newer Nordic devices. nRFconnect for Desktop has taken its place. I suggest when using the nRF52-DK (or any nRF52 based DK) that this newer utility be used.
The nRF51822 has been used successfully in many coin cell applications including beacons, wearable, etc. There were three versions of this device. Only REV 3 silicon is being shipped by Nordic. Any older parts should be avoided. If you are wondering what rev you have there is a chart in the compatibility section on the Nordic Semiconductor website. I would add that If supported by the sensors and such I would suggest looking as some of the newer parts in the nRF52 family. Some have a low membory variant that may work for you too. Using the DC/DC converter you can achieve about 6mA of receive and transmit current and sleep currents in the uA range and nA in power down.
@Jon-Raymond Correct. It is a nice product for the price and the intended user. As Jon mentioned, you can use the command line tools as well as nRFconnect and also has direct hooks into the Segger Embedded Studio which is a fully functional IDE / compiler/ Debugger and is free when used with Nordic Semi devices.
Plus there is no license conflict as there is when using one of these cheap overseas j-link knock offs. (Which could "break / brick" anytime doing a "official" Segger update on these clones.)
@Calvin-Khung
Jokgi
Jokgi about 2 hours ago
Calvin, You can buy a Nordic Development kit for about $50 dollars or less. It has the J-Link OB device on it for SWD programming and debugging.
Calvin, You cam buy a Nordic Development kit for about $50 dollars or less. It has the J-Link OB device on it for swd programming and debugging.
Hello,
I see two issues with this schematic. 1) The Cap C3 looks like it says 100nf. In the non-amplified use, this should be at least 4.7uF. If you are using a PA I would suggest a even larger value be used.
PO.25 and PO.26 if not used should be tied to ground. If used then they should each have a 12pF cap to ground. The internal bonding wires on the QFN package picks up some stray RF and will probably not pass any agency testing in Korea or Japan. This is probably not that important for personal use. 
@absolem Check out the css811 sensor. It can detect CO2 such as we al know we exhale with every breath. This is the same device used on the Nordic Semiconductor “nRF52 Thingy”.
@neverdie And it has the 32Khz crystal on it too which will reduce power consumption. And It looks like the DC/DC converter is also included?
@nca78 There is no downside to using the nRF52810. It depends on your needs. If you can live with 192K Flash and 24K RAM and a stack that supports peripheral only (at this time) then you are good. The device can use the internal 32Khz RC osc for BTLE and there is a slight current consumption hit as the receive window will be longer. (+/- 500ppm) . No different then on the nRF52832. as stated, a 32Khz crystal will give you a tighter clock and lower current consumption.
This is a scaled down version of the nRF52832 so there are some peripherals that have been taken out or reduced. PWM for example, only one. No NFC, 1x SPI Master or Slave, (instead of 3), No I2s...... The full datasheet and product briefs are available on Nordic's website so you can A-B the features.
@nca78 The Rev C (COO) parts are available now and they are the production parts. (Symmetry and Nordic's other distributors have these in stock) There will be a respin of this to a Rev D to fix the REG0 issue. FYI, the current nRF52840 package is not a WCSP. It is a aQFN
package. The nRF52840-Dongle is also available now. Go forth and design......
@alexsh1 These boards support the Jlink (Segger) environment. The Segger firmware is available for windows, linux and MacOS..https://www.segger.com/downloads/jlink/#J-LinkSoftwareAndDocumentationPa
@scalz 
I would be interested in any range testing in regard to this dongle. For ground it has whatever it is that it is plugged into. (PC, SBC, USB extention cable, etc) There will be a nRF52840 based dongle out soon. See picture above. This dongle will need to be programed over the SWD lines. No Segger on board this one..!
@artag The nRF51802 QFAA has 256k Flash and 16k RAM. It is pin to pin compatible with the nRF51822QFAA in the QFN48 package, 6x6 mm. Note that some of the parameters for the nRF51802 are slightly looser then the nRF51822. (Current consumption, wakeup time, sensitivity)
The nRF52-DK, nRF51-DK and nRF5284--PDK have a SWD / Debugger. They use the Segger OB Firmware in the Controller so it has the Jlink drag and drop feature. Has hooks to nRFJprog, and Keil and other IDE interfaces. They have on board nRF5x devices too if you want to use them for firmweare and hardware development. Arduino Uno format so standard shields can be used as well. On Sale at Semiconductorstore.com. $36 - $46 depending on version of board desired..
@neverdie The internal RC Osc will allow you to keep your BOM costs lower. However when using the Bluetooth Softdevice the Crystal will lower the power consumption as the BT window will be narrower.
@d00616 not familiar with the USB interface / tag connect. The ones I have used have the connector type that plugs onto the nRF5x-DK, uLinks, jlink lite, etc. a ten pin Micro Cortex connector to six or ten pin "pogo pin" tag-connect connector. There is also a clip that allows the connector to stay attached for debugging purposes.
@NeverDie check out a product called "TAG-CONNECT". It is perfect for programming. It is used on the Nordic Semiconductor Beacon Reference Design.
@Nca78 How about sending a email to the company and ask if there is a distributor / Rep in your area?
Dr. Yuan Fan
Fanstel Corp.
Trusted Name Since 1990
7466 E. Monte Cristo Ave., Scottsdale AZ 85260 USA
Tel. 1480-948-4928 x101;
email: yfan@fanstel.com http://www.fanstel.com
@miljume Are you using modules with the genuine Nordic Devices mounted on them? How do you have it connected? Are you successful with any other "compatible" modules?
@NeverDie Is this the board with a PA on it or stand alone nRF5x part? If with a PA what is the rated voltage of the device?
Depending on the Nordic part the nRF5x can run from 1.7 (or 1.8) to 3.6vdc. Note that the nRF51 cannot run with the DC / DC under 2vdc. The nRF52 does not have that restriction and the DC/DC can be used throughout the full voltage range..
@NeverDie 0_1508367805179_RD-nRF52-RFX2411N-REV2.zip Hello All -- For your viewing enjoyment. The Schematic and layout files for that nRF52840 and RFX2411n board you have. (If it is version 2 which did have the big Nordic logo on it. )
I think you may know this already but this bears repeating. This is not a Nordic board. Nordic Semiconductor's tech support will probably not know anything about this board. Also there is a difference between the RFX2411 and the nRF2411N. (N for Nordic) It is not the same device.
@NeverDie Hello, If you are referring to that Prototype Board with the Nordic logo on it then it was being controlled by GPIO and by the Bluetooth Low Energy stack (Softdevice) You can read more about it here.. https://devzone.nordicsemi.com/blogs/831/palna-support-in-s132/.
As I mentioned before. there is no good way to control the PA in a proprietary mode, only when using BLE. Regardless, I have asked if it is ok to share the schematic that relates to that PA board and I will let you all know. And about the question about antenna switching. This was never implemented in the Softdevice. Any antenna switching would need to be done in the application.
See if this chart helps.
@Jokgi The only datasheet I have states that it is confidential. Therefore I cannot share it. However if you contact Skyworks they may be able to get you a copy. At the time I received it one needed to fill out a form on RF Axis site and then the file would be sent. Are there any particular parameters you are interested in?
@NeverDie As I may have mentioned before. This was a limited run of prototypes (100 total) designed by RF AXIS and built by Xungtong.. My understanding is that this device is being deemphasized by Skyworks in favor of the SKY661xx family..
@NeverDie Note that all the nRF52840 based products being showcased now (including the Fanstel modules) are using the engineering silicon. There is Errata on these parts. Production devices will be available Q1-18.
@NeverDie You may wish to check out the nRF51 Reference guide in addition to the datasheet. http://infocenter.nordicsemi.com/pdf/nRF51_RM_v3.0.1.pdf The PPI is located in section 16.
@NeverDie The nRF51 is done on a different process then then the nRF52. The nRF52 is on average 50% lower power then the nRF51. The picture of the module shows a nRF51822QFAA Hx part which is a 256k flash, 16k Ram part REV 3. You can see all the revision number here: http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf51/dita/nrf51/compatibility_matrix/nRF51822_ic_revision_overview.html?cp=3_0_1
@NeverDie The really nice thing about the nRF52832 and other nRF52 variants is that running the BTLE stack (Softdevice ) you can run BTLE and proprietary somewhat simultaneously. You choose where you want to have them running this. Each node or just one for Smart Device connectivity.
@NeverDie Check out the new nRF52810. It is a stripped down version of the nRF52840.. Not as much memory and the peripherals are lower in count. But it has a Cortex M4 (Not F) and some of the targets are sensors, wearable, beacons, etc. On air compatible with nRF24L series and nRF52 series. Some limitations on BT 5.0 however.
@NeverDie from what I see in the picture of this module, it is using a Meandering Inverted F antenna. Part of that antenna is connected to ground. So you will measure a DC ground from anywhere along the antenna to ground.0_1507315872619_Ember -inverted F_120-5052-000_Designing_with_a_PCB_Antenna.pdf
@NeverDie Good catch!! The nRF52 series does not have this "feature". In other words, you don't have to bring the transmitter down to recalibrate the PLL..
Only nRF51 and nRF24xx and nRF24L series legacy devices require it.
@NeverDie I would use 3 ADDRESS bytes, for the reason I gave before. The receiver could see noise as a valid packet and try to process it. and the fact you have no data packet and no CRC could cause you issues in a noisy 2.4Ghz environment. . Also be aware that if the radio is not already in receive or transmit mode the PLL takes about 130us to come up and settle. Crystal start and settle time will also depend on the CL value of the Crystal and not all manufactures use the same value. Conversely you can only transmit packets for 4ms before you need to bring down the transmitter and bring it back up again for the PLL to start and settle.
@NeverDie I would not use a 2byte address for the reason I gave above. I was not including the preamble which is not really part of the address. 3 byte minimum is what I would recommend, not 2.
@d00616 You may wish to count your retries as well. It is no use keeping the window narrow if you need to keep transmitting and receiving to get the same packet across. It may show that having a little wider window reduces the average current required by increasing the chance of picking up the packet first time. If you are using a timer to synchronize the RX and TX (TDMA) then you may be just fine.
@NeverDie I would not go less then 3 address bytes or random noise may look like valid addresses. The more address Bytes the less chance of that happening.
@NeverDie If that is the case then I kind of limits their clientele a bit.
@NeverDie I believe that the Notwired price you mentioned was for the full dev kit board with RF module.
The Octotech device is not out in the market yet. I don't think they will be making production modules. Probably will have dev kits and then looking for module manufactures to produce modules with their part. 0_1507066567924_8TR8210 Product Brief RevA3.2.pdf
@NeverDie This module is based on the nRF52832 and a RF AXIS PA (now purchased by Skyworks) . I happen to have one of the first prototypes. This design worked great! . Note the blue wires attached to the 32khz crystal which was later mounted on the board.. Laughing a bit here. . 
@NeverDie Hi, Do you know how they are pulling in the PA on these nRF52832 modules? I see many people using the device in Proprietary mode. There is no hardware line like with the nRF24L & the nRF518xx devices.. (VDD_PA) The nRF52832 uses the Softdevice to control a external PA using GPIOs.. You can see them on this block diagram from the Notwired module . There will be a PA out soon from a new company called OctoTech that has a internal RF sense switch included in the part. This will make a straight PA design much easier. 
@Toyman there are both 5v and 3vdc available on the DK. You can use that to power the board. But that is not VTG line. That line just lets the DK know it has a target board out there and that the voltage is about 3vdc. (There are no voltage levelers on the board)
@NeverDie check out a Colorado company "Notwired". They have a 832 with a PA however I believe the PA is controlled by the softdevice. Check it out as there may be another way to contol it.
@Toyman What is the make and model of the module. You can use the nRF52-DK to erase the device. P20 is a ease access to the programming pins on that board. You need to power up the module, run the VDD from the module back to the dev kit , P20, Pin2. Hook up the SWDIO lines to Pin3 and the SWDCLK to Pin4. and Ground, Pin8. As reset is not hardwired you don't have to hook that up unless you want to (Pin7. .  You can use nRFJPROG to exersise the J-Link (Segger). This is found in the downloadable tools on the Nordic site. BTW - I have no problem using J-Link Commander version 6.20c with the nRF52-DK with the nRF52832 mounted. I hope this helped. 
@NeverDie This may be old news but I will throw it out anyway. The Reset pin on the nRF52 series is both a GPIO and RESET line (one or the other) . This is not a dedicated Reset however and the application must define that pin as RESET. This is the only pin that can be defined as reset. The Datasheet describes this as well.
@NeverDie Great Job!!!! Suggestion... If you are going to use the BTLE Softdevice you will have a smaller receive window if you use the external 32khz crystal option rather then the internal 32khz RC one. (+/- 20ppm with the crystal vs +/- 250 or 500ppm with the RC.
@Nca78 Corrrect. It seems to me that a < 50 dollar Nordic nRF52 based Dev kit (or similar) which can be updated would be much less hassle.
@NeverDie I am not sure about all the boards for sell on that site. but I would have to say that any J-link programmer that is packaged as such for $12-$40 dollars is probably counterfeit. Updating these items with newer J-link firmware would more then likely disable them. (On purpose) You may wish to contact Segger in Boston prior to spending money on these potential clones. I would be interested to hear what experiences other people have had with the products from that site.
The genuine J-link and j-link plus programmers are over $400.00 as you can see on the Digi-Key website. Per the Segger license agreements, the only J-link 0B devices that are able to be sold are to be bundled with a Evaluation / Development kit such as the nRF52-DK, ST, Rigato, and other semiconductor / module manufacture's dev kits.
@NeverDie Pretty much a reference only. In a previous post you inquired about the grounding on the meandering antenna. I posted the TI application note as a frame of reference only. However if you do create your own module you should be aware that the two matching components coming off the ANT pin are NOT antenna matching components but are three for output impedance matching and also acts as a low pass filter. Pi network is still required for tuning of the antenna. (may not use all three components after tuning)
@NeverDie someone did not read the datasheet. The harmonic filter / impedance matching network on the output of Pin 30 (ANT) is connected incorrectly. There needs to be abolded text Cap from ANT out to Pin 31 ONLY. (Not connected to any other ground pour as it seems they did here. Seems to be a few "extra components between there and the Antenna matching network too.
From the nRF52832 datasheet.
bolded text53.8 PCB layout example
The PCB layout shown below is a reference layout for the QFN package with internal LDO setup.
Important: Pay attention to how the capacitor C3 is grounded. It is not directly connected to the
ground plane, but grounded via VSS pin 31. This is done to create additional filtering of harmonic
components.[link text](link url)
@NeverDie nRFgo Studio uses the Segger J-link firmware. When using the Softdevice make sure that your application does not start below the top of the Softdevice or you will get a error on most programmers that there is something located in that protected space. If it does not see this as a protected area then you will corrupt the Softdevice.
Most programmers only need the two SWD lines, ground and a voltage reference from your target board back to the programmer. This is to tell the programmer you have a target board connected and what voltage it is running on. Note that the nRF52-DK does NOT have voltage translators on the programming lines (P19 and P20) so you must be powering your target boards with 3vdc to 3.3vdc. (I have tested down to 2.8vdc but it is not guaranteed to work consistently.) Not sure about ST or other programmers.
@NeverDie That is a meandered Inverted F Antenna (IFA). It will give you better performance then a standard meandering antenna and a much smaller size then a standard 1/4wave trace antenna. Not as easy to tune however. You can read about the one that TI designed for their 2.4Ghz dongle. http://www.ti.com/lit/an/swra117d/swra117d.pdf
Of course this is not Device dependent as you need to feed it with a 50 ohm feed point. A Pi network before between the Chip's ANT output and the Antenna is desired from a tuning standpoint.
Note that on the nRF52 designs, the two components (Cap and Inductor) connected to the ANT pin are used for harmonic filtering AND impedance matching and has nothing to do with the antenna tuning other to present a 50ohm feed point.
@gohan If you are using AutoAcks and you have a combination of True Nordic based Modules and nRF24L01P clones you may have a issue. Is there a way to not use acknowledgements and see if you can communicate properly between the modules?
@scalz the nRF52832 has a hotter receiver. ( better sensitivity.) at 1 mb/ s then the nRF24l series. Overall link Budget is better. 840 even better with a 8dB output.
@NeverDie you will need long range capabilities on both sides of the link. So two preview kits work great. Long range is supported by SDK 14 and the current softdevice.
@gohan a straight pig tail antenna of about 30mm should work fine (but will not be perfectly tuned).
@tcontrada I cannot say what their motivation is. I would imagine that the parts being made in China are still cheaper to manufacture. I am not hip to all the ways the Chinese government (State Capitalism) assists their companies but that may enter into the equations. (incentives, etc).
@tcontrada The flow of Nordic materials are as following : Wafer fabrication, packaging (QFN or WLCSP) test, then packaging (Tape & Reel or Tray). None of this is done in China. The finished goods are then sent to the authorized distributors worldwide for sale to manufactures. There are authorized distribution channels in China.
@alexsh1 Of course there is no requirement that they say who they are using. However If the parts are Genuine Nordic nRF24L01P then releasing the source of the Nordic devices should not be a issue as the authorized worldwide Nordic Semiconductor distributors are listed on the Nordic Semiconductor Web Site. So if the Manufacture of the modules were not forthcoming with the distributor used this would raise questions in my mind as to the history of the parts.
@parachutesj Unless you have the transmitter in constant carrier mode you cannot successfully measure the current with a standard multi-meter. If you want to know if the radio is transmitting and you have a good scope then look at the VDD_PA line.
@Oitzu Thanks for the follow up. Yes, the CE line is a input to the nRF24L01P. In the schematic sent yesterday it showed the CE line connected to the RXEN of the RFX2401c. Both are inputs.
@Jokgi @ all. Sorry I was not specific. I should have added Range measurements with and without the foil.
@Oitzu The pictures I have seen of various PA modules available on EBAY and such show a pretty solid ground pour on the top and bottom of the module. I am surprised that wrapping them with Au foil helped much. (But stranger things have been known to work. 
) Does anyone have some quantitative numbers with and without the foil mods?
@Oitzu
Is that the released schematic for that Module?
I can see why they have the resistor removed.
The CE line is a active high input to the nRF24L01P. The RXEN is a input to the RFX2401C used to switch in the different modes. (See the mode select table below)
The CE line could / should be controlled by the host MCU. You can see this on the state machine in the nRF24L01P datasheet section 6.1.1, Figure 4. The diagram shows recommended operating modes vs. possible operating modes.
For the RFX2401C,,,,
If the RXEN is pulled high with a resistor and when the nRF24L01P is not transmitting, the unit will switch the LNA in. In this setup the RFX never goes to shut down mode and the RFX is either in TX or RX mode. There are no internal pull ups or pull downs on the nRF24L01P CE or or the RFX devices RXEN. Therefore there is no guaranty that the lines will be high or low and could be subject to noise. I would not leave them floating.
Control Logic Truth Table X= Don't Care
TXEN RXEN 0perating Conditions
1 X TX Active
0 1 RX Active
0 0 Chip is Shut-down
To address the Current Draw. According to the RFX2401C datasheet, when the PA is transmitting at 20dBm the current consumption of the amp is 120mA. Plus whatever else you have running. (MCU, nRF24L01P, etc)
What is the PA used on the board? Are there schematics available? (Or a part number for the board) Are they using the VDD_PA line from the nRF24L01P to enable the PA? If so, scope out the VDD_PA line and see if it is toggling when transmitting. It will go high 50us before the nRF24L01p transmits a packet and will stay high the full time it is transmitting. If that line is not toggling when sending packets then you are not transmitting.
@tcontrada
You can purchase this part from Symmetry Electronics on line store for $1.78. That is single piece pricing. You may be certain that quantity pricing will be MUCH lower if you speak to a inside sales person.
I believe the hackaday reference was from Nordic. I just found this as well and is worth reading.
https://ncrmnt.org/2015/03/13/how-do-i-cost-optimize-nrf24l01/
"Looks like the answer why was at the very bottom of the comments of the Hack-A-Day comment feed discussing those fake ASICs. And the very comment was made made by someone from Nordic. Turns out that those clowns who made that ripoff ASIC brought a typo from the original specs to silicon, so the NO_ACK bit in the packet control field is inverted in the fake chips. Testing a little bit more – no matter whether the dynamic payloads are enabled or not, fakes will not be able to properly ack packets received from genuine devices, as well as those from nrf24lu1, nrf24le1. The reverse (surprise!) works!
If you thought that this is good news (we have a good way to distinguish fake and non-fakes) you are quite mistaken. Googling the internets I found at least 2 ‘compatible’ chips: SI24R01 and SE8R01. And forum threads indicate some differences in default pipe addresses after reset, so there may be even more of them. Maybe even those modules I have and consider ‘good’ are just better clones.
@Yveaux If the Chinese module has a genuine Nordic part on it then why would it not work? However there has been enough info put out there on the difference in the cloned parts and the genuine nRF24L01P device to know that there are incompatibilities in certain situations, like use of Auto-ACK on some of the clones. (Check out the hackaday posts on this activity. It is one thing when they sell the clones with the part number intact. It is another when they remove the markings and put nRF24L01+ on them. That is plain old Fraud and becomes counterfeiting.
@hek One should be able to change the Auto ACK register on one of the sides to make it work correctly. (If that is the type of clone being used as various clones have various differences) But that would mean tight control of what modules are being used with what firmware on what side of the link.
RF Digital makes a real nRF24L01P based module however it is more pricey then the Chinese knock offs. But if you only need a few of them then at least you know you are getting the real McCoy.
Has header and SMA connector
RFD21711
Has PCB antenna and header
RFD21712
This has no header and no SMA connector
RFD21716
The Nordic Website has all the Gerbers for this module in case you wish to roll your own.
http://www.nordicsemi.com/eng/nordic/download_resource/9620/7/13918708
If one wanted to make a tester out of a example this would work. http://www.nordicsemi.com/eng/nordic/download_resource/10638/11/57367651
However to run this example stock a nRF24LU1P dev kit is also required.