New file uploaded to [email protected]

[email protected] Notification

Hello,

This email message is a notification to let you know that a file has been uploaded to the Files area of the [email protected] group.

File: d4dqgreva.pdf

Uploaded By: Adam Rong

Description:
D4D Quick Guide Rev A - May 19, 2019.

You can access this file at the URL:
/g/crkits/files/D4D%20Kit%20Documentations/d4dqgreva.pdf

Cheers,
The Groups.io Team

New file uploaded to [email protected]

[email protected] Notification

#2595

Hello,

This email message is a notification to let you know that a file has been uploaded to the Files area of the [email protected] group.

File: d4dpartlist20190519forMP.xls

Uploaded By: Adam Rong

Description:
D4d part list 20m/40m for MP.

You can access this file at the URL:
/g/crkits/files/D4D%20Kit%20Documentations/d4dpartlist20190519forMP.xls

Cheers,
The Groups.io Team

Re: D4D: Documentations

#2594

开云体育

Software settings in Chinese. Try Google translation if you cannot fully understand from pictures.

Thanks,

Adam

在 2019年5月16日，上午8:05，Adam Rong via Groups.Io <rongxh@...> 写道：

Show quoted text

Folks,

I have created folders in the files and photos sections. I will update the files regularly.

/g/crkits/album?id=90325

/g/crkits/files/D4D%20Kit%20Documentations

Before the manual is published, you can refer to the step by step building photos here in Chinese:

?

Thanks,
Adam

Sorry, but we are not attending Hamvention this year

#2593

Folks,

Due to an unexpected reason, the show of D4D in Hamvention is cancelled. However, we believe that D4D is a promising product and you are welcome to introduce to your local clubs, forums or magazines.

The build and test by dozens of Chinese local hams went very well in the last a few days, and we also knew the limitations of this tiny product. I will start shipping from May 20. I hope you will like it.

Thanks,
Adam, BD6CR

D4D: Documentations

#2592

Folks,

I have created folders in the files and photos sections. I will update the files regularly.

/g/crkits/album?id=90325

/g/crkits/files/D4D%20Kit%20Documentations

Before the manual is published, you can refer to the step by step building photos here in Chinese:

?

Thanks,
Adam

IMD performance of D4D

#2591

Folks,

One of potential customers asked about the IMD performance and I think it is a good question. I have to clarify here when I wrote spurious suppression of -50dBc. It is actually for harmonics of 2nd and 3rd and other parasitic oscillations. If we check closely near the carrier frequency with a spectrum analyzer, the IMD products of 3rd, 5th are quite strong. The measured IMD 3rd is not good, which will generate strong overtone in waterfall spectrum and cause nearby channel interference. During design phase, I have noticed it but I have to balance the RF output from the design simplicity with this spec. I also noticed that the carrier leakage without audio modulation is strong too, and it is even higher than the 3rd IMD products.

Those are the facts and I hope you can understand and help improve if you can. Thank you.

--

Thanks,

Adam Rong

Re: D4D: Ready to Take Order

#2590

Very well. I have played music when dummy load is connected and it is quite high quality. However, you will need to inject quite high level volume (>600mV Vp) to activate VOX and you will need an external active speaker to be able to make voice QSO. An extra PTT may be required to enable/disable the microphone.

Thanks,

Adam

Show quoted text

On Tue, May 14, 2019 at 12:48 AM Casey via Groups.Io <kc9ih=[email protected]> wrote:

How well will these work on Voice (with a proper Freq Xtal)?

--

Thanks,

Adam Rong

Re: D4D: Ready to Take Order

#2589

How well will these work on Voice (with a proper Freq Xtal)?

Re: D4D: Ready to Take Order

#2588

Folks,

As I have promised, I created a button and you can order directly from my web site:

Due to the unexpected stability issue, I have to postpone the first shipment date from May 13 to May 20. Thanks for your understanding, and I wish to give you the best first impression.

BTW, I cannot offer blank PCB right now since all the parts are matched with the PCB quantity. I might reconsider later when I make the next lot.

Thanks,
Adam

Re: D4D: 20m version needs more time

#2587

开云体育

Folks,

I am pleased to announce that the issue was found. I will take time to verify the fix and the shipment will be pushed out for about a week. To play safe, I will check 40m as well. Sorry for the delay.

BTW, I got crystals for 3.573 today and 80m version will be in plan.

Thanks,

Adam

在 2019年5月11日，下午11:40，Adam Rong via Groups.Io <rongxh@...> 写道：

Show quoted text

Folks,

As I tested building 20m version one more time and I still found a little bit self-oscillation. As I said this is the nature of this architecture to use only one NE602 for both RX and TX. AA7EE also mentioned about this when he was building his DSB radios:

I had thought I found a perfect fix by muting the front end but it seems not working very stable for 20m as the frequency is higher and the self-oscillation gets easier, I suppose.

What I am going to do, is that I will hold the shipment and announcement for 20m version before the actual shipment starts. I will need about one week to find a proper fix. If it does not happen, I will ask if you would like to switch to 40m or accept refund.

The 40m version is stable and I think you will enjoy this tiny radio to make dozens of QSO’s.?

Thanks,
Adam

Re: D4D: Ready to Take Order

Mark KG5SPO

#2586

Can I buy a few of the blank PC cards from you, if so how?much?

Mark Schiff

Show quoted text

On Wed, May 8, 2019 at 10:24 AM Adam Rong <rongxh@...> wrote:

Folks,

I start to take email order now. The introductory price is 39 USD for kit including shipping to worldwide. As in the introductory period, you will get audio cable options for free. The earliest possible shipment date is now improved to May 13.

You can directly PayPal to rongxh@...?and let me know 40m or 20m (80m not ready yet). I will ship based on the sequence of receiving your payment. I may delay shipment for one week or two due to workload.

This is the spec so far:

Summary: Crystal controlled single frequency DSB transceiver for 20m (14.074MHz), 40m (7.074MHz) or 80m (3.573MHz), other frequencies could be added per request
Power supply: 10-14V DC regulated power supply or battery pack, 12V is recommended, center positive, reverse polarity protection available
Current consumption in RX: about 15mA at 12V
Current consumption in TX: about 300mA at 12V
RF output: about 1W for 40m band at 12V, and a bit less for 20m band
Spurious suppression: no worse than -50dBc
Antenna connector: BNC connector, 50 ohm
Audio in connector: 3.5mm mono, at least 600mV to activate VOX, connects to headphone connector at PC sound card, no dedicated PTT connector is required
Audio out connector: 3.5mm mono, connects to microphone connector at PC sound card
Amber LED: TX status
Green LED: RX status
Frequency accuracy: -600 Hz ~ + 200 Hz
Frequency stability: Okay for FT8 mode per test. If the optional heater resistor R20* is added, after warm up, long term frequency stability in 10 min will be improved at the cost of acceptable short term frequency stability sacrifice in 30 sec.

Thanks,
Adam

D4D: 20m version needs more time

#2585

开云体育

Folks,

As I tested building 20m version one more time and I still found a little bit self-oscillation. As I said this is the nature of this architecture to use only one NE602 for both RX and TX. AA7EE also mentioned about this when he was building his DSB radios:

I had thought I found a perfect fix by muting the front end but it seems not working very stable for 20m as the frequency is higher and the self-oscillation gets easier, I suppose.

What I am going to do, is that I will hold the shipment and announcement for 20m version before the actual shipment starts. I will need about one week to find a proper fix. If it does not happen, I will ask if you would like to switch to 40m or accept refund.

The 40m version is stable and I think you will enjoy this tiny radio to make dozens of QSO’s.?

Thanks,

Adam

Re: D4D: Ready to Take Order

#2584

Hello.I'm waiting for you to complete the tests, and I'm sure to order.Best regards.

Re: D4D: Ready to Take Order

#2583

开云体育

Good news: 10130 can be pulled to around 10135.5 and it is good enough to cover 30m FT8 band. I will run more tests to make sure it is stable.

Thanks,

Adam

在 2019年5月10日，下午11:34，Adam Rong via Groups.Io <rongxh@...> 写道：

Show quoted text

I have found crystals of 10.140 and 10.130. I’ll see if it is good to be pulled. If they cannot be pulled, 10.130 will be good for JS8CALL.

Thanks,
Adam

在 2019年5月10日，下午3:01，Furtuna Mircea via Groups.Io <mircea99fm@...> 写道：

Hello Adam.Which crystals (frequent) can be added?
I'm especially interested in 10mhz (30 meter band).Mircea-YO9IOF

Re: D4D: Ready to Take Order

#2582

开云体育

I have found crystals of 10.140 and 10.130. I’ll see if it is good to be pulled. If they cannot be pulled, 10.130 will be good for JS8CALL.

Thanks,

Adam

在 2019年5月10日，下午3:01，Furtuna Mircea via Groups.Io <mircea99fm@...> 写道：

Show quoted text

Hello Adam.Which crystals (frequent) can be added?
I'm especially interested in 10mhz (30 meter band).Mircea-YO9IOF

Re: D4D: Ready to Take Order

#2581

Hello Adam.Which crystals (frequent) can be added?
I'm especially interested in 10mhz (30 meter band).Mircea-YO9IOF

Re: DSB transceiver for Digital mode

#2580

Personally I will build a few. Please contact offline for the availability. Please add $25 for the build service.

Thanks,

Adam

Show quoted text

On Fri, May 10, 2019 at 2:45 AM wohlsson . <wohlsson@...> wrote:

Hi Adam...will there be any pre-assembled ones available??

Thanks

Bill...wa8bda

Virus-free.

On Wed, May 8, 2019 at 7:58 PM Adam Rong <rongxh@...> wrote:
Ron,

Pulling with NP0 capacitors will not generate too much stability issue. Normally inductors are drifting much. However, you are correct that 20m crystal is more unstable, but with the heating solution, it is much better and it won't have problem to make QSO. Adding heating resistor does have limitations, for example, if you use with car battery, the voltage varies with charging and the crystal frequency will vary as well. That's why we need regulated power supply or battery pack.

I customize all the crystals from a reliable supplier.My crystals for KN-Q7A, CS-series, CRK-10A all come from them.

I have all the parts ready and ready to ship hundreds of kits now. The first batch is 350 kits. Let's see how soon it will be gone.

Thanks,
Adam

On Thu, May 9, 2019 at 6:50 AM Ron Stone <rsstone2@...> wrote:
Adam,

Thanks for your helpful, informative responses.

So it sounds like the 40 meter version may be significantly more stable than the 20 meter version because of the lower frequency crystal.? In addition, the 40 meter crystal doesn't have to be pulled like the the 14.070 MHz crystal which eliminates another possible source of instability, correct?? Does this mean the heating resistor is more optional for 40 meters?

Also, what is your source for the 7.074 MHz crystals?

Thanks again for your help and I'm glad to see we can order now!

73,

Ron (KA3J)

--
Thanks,
Adam Rong

--

Thanks,

Adam Rong

Re: DSB transceiver for Digital mode

#2579

Hi Adam...will there be any pre-assembled ones available??

Thanks

Bill...wa8bda

Virus-free.

Show quoted text

On Wed, May 8, 2019 at 7:58 PM Adam Rong <rongxh@...> wrote:

Ron,

Pulling with NP0 capacitors will not generate too much stability issue. Normally inductors are drifting much. However, you are correct that 20m crystal is more unstable, but with the heating solution, it is much better and it won't have problem to make QSO. Adding heating resistor does have limitations, for example, if you use with car battery, the voltage varies with charging and the crystal frequency will vary as well. That's why we need regulated power supply or battery pack.

I customize all the crystals from a reliable supplier.My crystals for KN-Q7A, CS-series, CRK-10A all come from them.

I have all the parts ready and ready to ship hundreds of kits now. The first batch is 350 kits. Let's see how soon it will be gone.

Thanks,
Adam

On Thu, May 9, 2019 at 6:50 AM Ron Stone <rsstone2@...> wrote:
Adam,

Thanks for your helpful, informative responses.

So it sounds like the 40 meter version may be significantly more stable than the 20 meter version because of the lower frequency crystal.? In addition, the 40 meter crystal doesn't have to be pulled like the the 14.070 MHz crystal which eliminates another possible source of instability, correct?? Does this mean the heating resistor is more optional for 40 meters?

Also, what is your source for the 7.074 MHz crystals?

Thanks again for your help and I'm glad to see we can order now!

73,

Ron (KA3J)

--
Thanks,
Adam Rong

Re: DSB transceiver for Digital mode

#2578

Ron,

Pulling with NP0 capacitors will not generate too much stability issue. Normally inductors are drifting much. However, you are correct that 20m crystal is more unstable, but with the heating solution, it is much better and it won't have problem to make QSO. Adding heating resistor does have limitations, for example, if you use with car battery, the voltage varies with charging and the crystal frequency will vary as well. That's why we need regulated power supply or battery pack.

I customize all the crystals from a reliable supplier.My crystals for KN-Q7A, CS-series, CRK-10A all come from them.

I have all the parts ready and ready to ship hundreds of kits now. The first batch is 350 kits. Let's see how soon it will be gone.

Thanks,

Adam

Show quoted text

On Thu, May 9, 2019 at 6:50 AM Ron Stone <rsstone2@...> wrote:

Adam,

Thanks for your helpful, informative responses.

So it sounds like the 40 meter version may be significantly more stable than the 20 meter version because of the lower frequency crystal.? In addition, the 40 meter crystal doesn't have to be pulled like the the 14.070 MHz crystal which eliminates another possible source of instability, correct?? Does this mean the heating resistor is more optional for 40 meters?

Also, what is your source for the 7.074 MHz crystals?

Thanks again for your help and I'm glad to see we can order now!

73,

Ron (KA3J)

--

Thanks,

Adam Rong

Re: D4D: Ready to Take Order

#2577

I will create a button and put on my web site this weekend but I am still on travel. I have received 5 orders so far and please continue to use rongxh@... to PayPal.

Thanks,

Adam

Show quoted text

On Thu, May 9, 2019 at 5:11 AM John M <kf6efg@...> wrote:

Do you have a link to your paypal?

--

Thanks,

Adam Rong