Date   

Re: From Bob AF2DX

Adam Rong
 

Hi Bob,

Good to hear from you again. Take care of yourself and your family.

Here in China, it is a national holiday equivalent to July 4 in US. We have several days off, so we will plan for a family trip driving my car.

Thanks,
Adam

在 2017年10月2日,下午11:26,beargyrils@... [CHINA_QRP] <CHINA_QRP@...> 写道:

 

Still here but in the hospital again with my HB1B QRP radio To much QRM but copy strong stations OK. 73 BoB AF2DX
Sent from my Verizon Wireless BlackBerry


From Bob AF2DX

 

Still here but in the hospital again with my HB1B QRP radio To much QRM but copy strong stations OK. 73 BoB AF2DX
Sent from my Verizon Wireless BlackBerry


Re: TXCO with CS-Series Transceiver?

Adam Rong
 

John,

Of course it will work with a TCXO if you need better stability. TCXO is an active crystal, and the accuracy is very high, so I suppose there is no need for calibration.

Thanks,
Adam

在 2017年10月2日,下午10:32,landrjoh@... [CHINA_QRP] <CHINA_QRP@...> 写道:

 

Hi Adam,


What considerations should be made to replace the stock crystal oscillator with a TXCO (Temperature Controlled Crystal Oscillator) on the Sandwich VFO for greater frequency stability when operating on digital modes?


Can the frequency of the Sandwich VFO oscillator be safely changed if needed?  Lower?  Higher?


Thank you,


John

AA7US


TXCO with CS-Series Transceiver?

AA7US
 

Hi Adam,


What considerations should be made to replace the stock crystal oscillator with a TXCO (Temperature Controlled Crystal Oscillator) on the Sandwich VFO for greater frequency stability when operating on digital modes?


Can the frequency of the Sandwich VFO oscillator be safely changed if needed?  Lower?  Higher?


Thank you,


John

AA7US


Re: Pixie2 on Choc Perfboard

AA7US
 

Adam,

I don't know if it's just me, but I'm not seeing any pictures of your Pixie2 project with your message here on the CHINA_QRP Yahoo forum.

73,

John
AA7US


---In CHINA_QRP@..., <rongxh@...> wrote :

I made this popular CW radio on 2 units of Choc Perfboard today.


Pixie2 on Choc Perfboard

Adam Rong
 

Gang,

I made this popular CW radio on 2 units of Choc Perfboard today. The circuit has a 2N3906 acting as TX/RX offset as well as sidetone control (which is my modification). I plan to add a OMRON switch on the board to make it self contained CW key.

As you can see on the bottom side, there are quite a few solder bridges and short jumpers for connection purposes, but there are no long wire jumpers.

If you are interested, I can make a board kit at low cost at 7.99 USD including basic air shipping (2-4 weeks) or 9.99 USD including priority air shipping (1-3 weeks).

Thanks,
Adam


Re: KN-Q7A VRS CS

n7rgw
 

You can make the conversion, but it might be more fun to just buy a CS-15/17 radio.  The filters are different and it is difficult to remove the DIY7-7 coils and replace them with DIY7-21 as well as the associated capacitors.
One thing that you might consider is my dual band option for a KN-Q7A or a CS-series radio.  It comes with the filters needed.  However, I have not checked out the 15 or 17 Meter filters, yet.  I will be doing that this week or next week, I hope.
But you can add the Sandwich to your radio now and get that part of the conversion working.  The Sandwich will give you full band coverage instead of partial band coverage.  You can order that from CRKITS.com or from me in the US.
My add: visit www.QRVTronics.com.


Re: KN-Q7A VRS CS

Adam Rong
 

Hi Mike,

It is possible to make the modification. Likely you will get about 2 watt PEP on 15 meter band. You will need to order the following from CRKITS.COM offline:
1 pcs 15m Sandwich digital VFO complete kit for IF 8.192 (please confirm IF)
4 pcs DIY7-21 coils to replace DIY7-7 (you don't need to replace the reworked DIY7-7*, do it carefully when you desolder)
4 pcs 150 pF cap to replace 470 pF in LPF
Reduce both T37-2 toroids winding from 15 turns to 8 turns in LPF
4 pcs 15 pF cap to replace 27 pF in both RX and TX BPF
2 pcs 3 pF cap to replace 2 pF in both RX and TX BPF
1 pcs BD139 driver transistor to replace D882
1 pcs IRF510 final MOSFET to replace IRF530
Total 32 USD including shipping. PayPal rongxh@...

Thanks,
Adam

于 2017-9-30 18:13, mikeymustang2000@... [CHINA_QRP] 写道:

 

Group,


I have an old KN-Q7A that was on 7MHZ and I want to convert it to 21MHZ. I seen that the CS series possibly can do 21 MHZ and the CS Looks very similar.can I buy a CS lit for 21 MHZ and convert my KNQ7A?


Thank you


Mike WA3O



KN-Q7A VRS CS

Mike
 

Group,


I have an old KN-Q7A that was on 7MHZ and I want to convert it to 21MHZ. I seen that the CS series possibly can do 21 MHZ and the CS Looks very similar.can I buy a CS lit for 21 MHZ and convert my KNQ7A?


Thank you


Mike WA3O


Re: CS-60?

n7rgw
 

Attached is a bandplan for the US, but there are also several other frequencies that also might open up.


On Saturday, September 23, 2017 2:47 AM, "Adam Rong rongxh@... [CHINA_QRP]" wrote:


 

Gang,

Recently I heard China is going to open 60 meter amateur radio band as well, with the power limit of 15 watt (EIRP). I suppose CS-series would be good for this purpose. As I am not very clear about the band plan for each country, I would like to hear from your ideas.

Thanks,
Adam




Re: CS-60?

AA7US
 

Adam,

Here in the USA, the 60M band is comprised of 5 each 2.8 kHz wide "channels" centered on 5.332, 5.348, 5.358, 5.373 and 5.405 MHz.  Since the FT8 digital mode is currently being conducted on the 5.358 MHz channel, that's the one I'd opt for if I had a CS-60. 

Of course it'd be easy to reprogram the Sandwich VFO to change channels.

73,

John
AA7US
 

---In CHINA_QRP@..., <rongxh@...> wrote :

Gang,

Recently I heard China is going to open 60 meter amateur radio band as well, with the power limit of 15 watt (EIRP). I suppose CS-series would be good for this purpose. As I am not very clear about the band plan for each country, I would like to hear from your ideas.

Thanks,
Adam


Re: Chinese Pixie and Frog Sound

Adam Rong
 

Chris,

Thanks for coming back. After receiving my Master of Engineering degree in computer science, I started my career from 2003 as a project manager to develop laptop products (like ThinkPad SL series) in Lenovo, and later on I also worked for Sun Microsystems and HP to develop servers, storages, and tablets. Now I am working for a Chinese customer drone (quadcopter) company as both a project manager and an engineering manager of Electrical Engineering. Now I work about 55 hours a week for this job.

This kit business is my side business and I still play solo, which means that I do everything including design, test, purchasing, kitting, test building, manual writing, video shooting, web design and maintenance, promotion and customer service etc. I make very little mistake while kitting because I almost can recite everything, and I never do advertisement because I believe mouth-to-mouth introduction is good enough to bring enough business for my spare time. I try to maintain good quality and service standard so we can keep our customers happy. I appreciate my distributors and customers' great support, so I can continue, and hopefully it is meaningful to do so.

Thanks,
Adam

在 2017年9月23日,下午6:04,Christopher Leslie chrisrleslie@... [CHINA_QRP] <CHINA_QRP@...> 写道:

 

Hi Adam,

Thanks for sharing.   What is your professional work?  I always assumed that your kits were your primary business/work.  It never occurred to me that you may have a different job.  

Chris 


On Sep 23, 2017, at 04:16, Adam Rong rongxh@... [CHINA_QRP] <CHINA_QRP@...> wrote:

 


Gang,

I found many videos on YouTube about these very low cost Chinese QRP kits. As a benefit of this group, I would like to introduce a little bit about the background.

Back in 2000, when I was still a graduate school student in university, I started to translate and adapt popular QRP designs to Chinese hams. I wrote a few articles to local magazines about the original design and what we can do to build with easy-to-find Chinese parts. BG6QBY and I worked together to make a few Chinese version kits for local hams for a few years. BA6QH, one of the most famous QRP'ers in China, actively promoted these small kits and we renamed these kits like leather shoes (Pixie in Chinese pronunciation), Frog sound (in one of my early articles to introduce 40-9'er, I wrote, I remembered the summer night in hometown where I can hear frog croaks. Now the field of the Chinese QRP is still quite silent and I wish the popularity of this design can create many frog croaks), Octupus (because the cables of my homemade case for the original Small Wonder Labs RockMite looks pretty much like an octopus, and later on someone also named as Super RockMite or something for BD4RG's modification, and this is the previous versions for CRK-10A) and etc. Since these kits are so well known in China, now these kits are made by many others (but no more by BG6QBY or myself), some of them are not really radio amateurs.

You will also find that these QRP kits will normally operate at 7.023 MHz because it is the QRP frequency in China.

After many years of pause, I restarted to write introductory articles this year. I introduced the Knobless Wonder and BITX-40. However, I don't have plan to offer kits this time because I am very busy with my professional work.

Thanks,
Adam


Re: Chinese Pixie and Frog Sound

Christopher Leslie
 

Hi Adam,

Thanks for sharing.   What is your professional work?  I always assumed that your kits were your primary business/work.  It never occurred to me that you may have a different job.  

Chris 


On Sep 23, 2017, at 04:16, Adam Rong rongxh@... [CHINA_QRP] <CHINA_QRP@...> wrote:

 


Gang,

I found many videos on YouTube about these very low cost Chinese QRP kits. As a benefit of this group, I would like to introduce a little bit about the background.

Back in 2000, when I was still a graduate school student in university, I started to translate and adapt popular QRP designs to Chinese hams. I wrote a few articles to local magazines about the original design and what we can do to build with easy-to-find Chinese parts. BG6QBY and I worked together to make a few Chinese version kits for local hams for a few years. BA6QH, one of the most famous QRP'ers in China, actively promoted these small kits and we renamed these kits like leather shoes (Pixie in Chinese pronunciation), Frog sound (in one of my early articles to introduce 40-9'er, I wrote, I remembered the summer night in hometown where I can hear frog croaks. Now the field of the Chinese QRP is still quite silent and I wish the popularity of this design can create many frog croaks), Octupus (because the cables of my homemade case for the original Small Wonder Labs RockMite looks pretty much like an octopus, and later on someone also named as Super RockMite or something for BD4RG's modification, and this is the previous versions for CRK-10A) and etc. Since these kits are so well known in China, now these kits are made by many others (but no more by BG6QBY or myself), some of them are not really radio amateurs.

You will also find that these QRP kits will normally operate at 7.023 MHz because it is the QRP frequency in China.

After many years of pause, I restarted to write introductory articles this year. I introduced the Knobless Wonder and BITX-40. However, I don't have plan to offer kits this time because I am very busy with my professional work.

Thanks,
Adam


Chinese Pixie and Frog Sound

Adam Rong
 

Gang,

I found many videos on YouTube about these very low cost Chinese QRP kits. As a benefit of this group, I would like to introduce a little bit about the background.

Back in 2000, when I was still a graduate school student in university, I started to translate and adapt popular QRP designs to Chinese hams. I wrote a few articles to local magazines about the original design and what we can do to build with easy-to-find Chinese parts. BG6QBY and I worked together to make a few Chinese version kits for local hams for a few years. BA6QH, one of the most famous QRP'ers in China, actively promoted these small kits and we renamed these kits like leather shoes (Pixie in Chinese pronunciation), Frog sound (in one of my early articles to introduce 40-9'er, I wrote, I remembered the summer night in hometown where I can hear frog croaks. Now the field of the Chinese QRP is still quite silent and I wish the popularity of this design can create many frog croaks), Octupus (because the cables of my homemade case for the original Small Wonder Labs RockMite looks pretty much like an octopus, and later on someone also named as Super RockMite or something for BD4RG's modification, and this is the previous versions for CRK-10A) and etc. Since these kits are so well known in China, now these kits are made by many others (but no more by BG6QBY or myself), some of them are not really radio amateurs.

You will also find that these QRP kits will normally operate at 7.023 MHz because it is the QRP frequency in China.

After many years of pause, I restarted to write introductory articles this year. I introduced the Knobless Wonder and BITX-40. However, I don't have plan to offer kits this time because I am very busy with my professional work.

Thanks,
Adam


CS-60?

Adam Rong
 

Gang,

Recently I heard China is going to open 60 meter amateur radio band as well, with the power limit of 15 watt (EIRP). I suppose CS-series would be good for this purpose. As I am not very clear about the band plan for each country, I would like to hear from your ideas.

Thanks,
Adam


Frequency Display for Sandwich

n7rgw
 

I am announcing the availability of three new kits which when added to the Sandwich will give Frequency Readout.

If you have any questions, please let me know.  An upgrade to the Sandwich code is required and is available at QRVTronics.com 


Re: JT9A and OLED Digital Display [1 Attachment]

Adam Rong
 

Digital modes are a lot of fun, and CS-series or KN-Q7A plus Sandwich digital VFO works great so far with the specially made firmware by JH3BTK.

Larry's modification to add a OLED display seems to be quite promising. My personal preference is the same as yours - the smaller one - so you don't have to move the IF GAIN potentiometer.

Thanks,
Adam

在 2017年9月17日,上午12:12,landrjoh@... [CHINA_QRP] <CHINA_QRP@...> 写道:

 

Hey Gang,

Last night I tried out the JT9A digital mode using my CS-40 (40M band).  The farthest QSO achieved using about 7 to 8 watts TX power was 4049 km (2516 miles).

My CS-40 has a FT50-43 final toroid (T3) installed in place of the original (FT37-43).  It had no problem with JT9A long transmit time of 49 seconds.  The enclosure barely became warm to the touch.  It helps that JT9A has an "off" (RX) period of 71 seconds after each TX period.  BTW, the bandwidth of a JT9A signal is only 15.6 Hz wide!

The sketch being used in the sandwich VFO for this CS-40 is been modified by JH3BTK to support dual BFO's to select either LSB (default) or USB using a 1/2 second press of tuning knob.  Also added to the sketch is code written by N7RGW Larry Lovell of QRVTronics to support a mini-OLED frequency display.

A picture of my CS-40 with the QRVTronics mini-OLED frequency display is attached.

73,

John
AA7US


JT9A and OLED Digital Display

AA7US
 

Hey Gang,

Last night I tried out the JT9A digital mode using my CS-40 (40M band).  The farthest QSO achieved using about 7 to 8 watts TX power was 4049 km (2516 miles).

My CS-40 has a FT50-43 final toroid (T3) installed in place of the original (FT37-43).  It had no problem with JT9A long transmit time of 49 seconds.  The enclosure barely became warm to the touch.  It helps that JT9A has an "off" (RX) period of 71 seconds after each TX period.  BTW, the bandwidth of a JT9A signal is only 15.6 Hz wide!

The sketch being used in the sandwich VFO for this CS-40 is been modified by JH3BTK to support dual BFO's to select either LSB (default) or USB using a 1/2 second press of tuning knob.  Also added to the sketch is code written by N7RGW Larry Lovell of QRVTronics to support a mini-OLED frequency display.

A picture of my CS-40 with the QRVTronics mini-OLED frequency display is attached.

73,

John
AA7US


Re: Troubleshooting the CS-40

John VA7JBE
 

Thanks for the advice.  I traced back and found an old fix that I did about 2 months ago (when I last worked on the kit.)  One of the leads for the crystal in the single pole IF amp filter had broken off during shipping and I had bridged it with a jumper.  I removed the jumper and the voltages are pretty close to where they should be:

Pin   Volts
1      1.35
2      1.22
3      0
4      5.87
5      6.8
6      7.33
7      7.27
8      8

Still not sure whats up with the relays, but I'm thinking of ordering some new ones when I order a new IF filter crystal.

John VA7JBE


Re: Troubleshooting the CS-40

AA7US
 

John,

Unless I'm mis-reading the schematic, there definitely shouldn't be 8v DC on pin 1.  8v DC on pin 8 is normal.

I think now I'd carefully work back from pin 1 along the affected circuit to try and find out how (where) that 8v DC is coming from.

Question: Did the transceiver work fine for awhile then suddenly start acting up like this?  Or has this been a problem since you assembled it?

John
AA7US

---In CHINA_QRP@..., <va7jbe@...> wrote :

I'm afraid I don't have a second mixer IC, but I pulled off the one giving weird readings and measured the voltage on the pins.  All pins are 0 volts except 1 and 8, which were 8 volts.

John VA7JBE