Date   
Re: dB level and TX timings

Adam Rong
 

Hi Conor EI6GSB,

Thanks for reporting this. I have never met this before. If you have spare part, you can try to swap NE602 to see if it is better. Also, check if you have properly attach the final transistor to the rear cover to help heat sink.

Thanks,
Adam

Thanks,
Adam


On Mon, Aug 5, 2019 at 2:32 AM <conchobhair.ofearghail@...> wrote:
Hi all again,

After some more investigation I believe this simply may be a case of the transceiver overheating. I opened the case to inspect the board to see if there were any signs of component damage, and everything looked fine. I powered up the transceiver and I still experienced the original problem, but after a few minutes the TX timings returned to normal and the dB level dropped down to about 23dB.

My radio shack got very warm over the last couple of days (over 30 degrees C) and I while troubleshooting I opened the door to let the room cool down for my own personal comfort. I think that this, combined with the black, heat-absorbing enclosure of the transceiver caused the components on the board to overheat and not function correctly.

Thanks to the nature of the enclosure and the board, the D4D transceiver may lend itself to a cooling system modification for people operating in unusually warm climates.

Thank you, too, to Adam for developing the kit: it was fun to assemble and I'm looking forward to making some QRP contacts!

73,
Conor EI6GSB



--
Thanks,
Adam Rong

Re: D4D mods

Simon C <symen79@...>
 

What diode is recommended for Steve's Mod?

Re: D4D mods

Adam Rong
 

In my test, I used 1N4148 but any diode will do, like 1N914, 1N4001-4007, 1N5817 and etc.

On Mon, Aug 5, 2019 at 8:12 AM Simon C via Groups.Io <symen79=yahoo.com@groups.io> wrote:
What diode is recommended for Steve's Mod?



--
Thanks,
Adam Rong

d4d off frequency

ron mcmurray
 

my d4d is off frequency, low by 2khz . do i decrease or increase capitance. it's at 14.272.
thanks, ron
kc0tdj

Re: d4d off frequency

Adam Rong
 

Ron,

If you measure by a frequency counter or other devices with a probe, the capacitance introduced by the probe will pull low the oscillator frequency, and 2kHz is a reasonable number.

You can receive the same station using D4D and a known calibrated commercial radio to know the difference.

Thanks,
Adam

在 2019年8月6日,上午7:44,ron mcmurray <hamshack@...> 写道:

my d4d is off frequency, low by 2khz . do i decrease or increase capitance. it's at 14.272.
thanks, ron
kc0tdj

New Facebook Group for D4D

Adam Rong
 

Folks,

You are invited to join the new group.
https://www.facebook.com/groups/487925331780070/

Thanks,
Adam

Re: d4d off frequency

ron mcmurray
 

i used my k2 to measure it.

Re: New Facebook Group for D4D

Bryan Brauer
 

Adam,

I surely hope that this will not be the sole, or even primary venue for information exchange.  I do not do, and never will do, Facebook.

Bryan B. Brauer, PE
Consulting Engineer


On Mon, Aug 5, 2019 at 8:47 PM Adam Rong <rongxh@...> wrote:
Folks,

You are invited to join the new group.
https://www.facebook.com/groups/487925331780070/

Thanks,
Adam

Re: New Facebook Group for D4D

Adam Rong
 

Bryan,

I have a WECHAT group for domestic hams to real time discuss about D4D kit building, modification and application. Facebook group will serve as the same function for international hams.

I will still keep this groups.io group the major area for announcements and file keeping.

Thanks,
Adam

在 2019年8月7日,上午12:21,Bryan Brauer <bryan@...> 写道:

Adam,

I surely hope that this will not be the sole, or even primary venue for information exchange.  I do not do, and never will do, Facebook.

Bryan B. Brauer, PE
Consulting Engineer


On Mon, Aug 5, 2019 at 8:47 PM Adam Rong <rongxh@...> wrote:
Folks,

You are invited to join the new group.
https://www.facebook.com/groups/487925331780070/

Thanks,
Adam

Re: d4d off frequency

Adam Rong
 

Ron,

Since the info is limited, I have to guess.

I suppose you have calibrated K2 frequency. Please confirm you did like one of these ways:
1. Use zero beat to test the carrier leakage from the D4D oscillator.
2. If you send 1500 Hz audio into D4D and triggered VOX, your K2 should zero beat two most strong frequencies at 14.0755 and 14.0725 MHz.
3. Send FT8 signal and receive in K2 and compare the audio frequency delta.

Thanks,
Adam


On Tuesday, August 6, 2019, ron mcmurray <hamshack@...> wrote:
i used my k2 to measure it.



--
Thanks,
Adam Rong

Re: d4d off frequency

ron mcmurray
 

dont know what i did but its working on frequency now.
thanks for your help.
ron, kc0tdj

Re: New Facebook Group for D4D

bleepingbeep
 

I agree with Mr. Brauer.  Groups.io is an international venue, is it not?

Jerry AA6KI
Tucson

D4D 20m kit for sale

bleepingbeep
 

I am offering my unbuilt D4D kit for sale.  It is the 20m version, and the price is $35 shipped.  U.S. addresses and PayPal only, please.

Jerry AA6KI
Tucson

Re: New Facebook Group for D4D

Adam Rong
 

Don’t worry. I meant Facebook group is a new one, but it won’t replace here.

Thanks,
Adam

在 2019年8月7日,下午11:14,bleepingbeep <bleepingbeep@...> 写道:

I agree with Mr. Brauer.  Groups.io is an international venue, is it not?

Jerry AA6KI
Tucson

Re: d4d off frequency

ron mcmurray
 

found the problem. power socket is off center in hole when in the case. grounding the collector of q4.  i put a nylon screw in to cure it. socket is flat on the board its built a little off i guess.
ron, kc0tdj

Re: d4d off frequency

Adam Rong
 

Ron, I don’t understand the point. This is nothing to do with frequency accuracy. Also, nylon screw is not necessary if you follow my instructions to build.

Thanks,
Adam

在 2019年8月8日,上午4:56,ron mcmurray <hamshack@...> 写道:

found the problem. power socket is off center in hole when in the case. grounding the collector of q4.  i put a nylon screw in to cure it. socket is flat on the board its built a little off i guess.
ron, kc0tdj

Re: d4d off frequency

ron mcmurray
 

the barrel or the power connector was touching the plated thru hole of the back plate.the screw in q4 grounds the collector to the back plate. it messed with the voltage,not sure if frequency was off or it just was not working right. easier to use nylon screw than try to make hole bigger
ron kc0tdj

Re: d4d off frequency

Adam Rong
 

The barrel or the external ring of the power connector should be grounded so it is okay to touch the plated dc jack hole.

For TO-126 package transistors like Q4, the hole has insulation already so a metal screw and a thermal pad will do the work of insulation from the PCB panel.

Thanks,
Adam

在 2019年8月8日,下午10:17,ron mcmurray <hamshack@...> 写道:

the barrel or the power connector was touching the plated thru hole of the back plate.the screw in q4 grounds the collector to the back plate. it messed with the voltage,not sure if frequency was off or it just was not working right. easier to use nylon screw than try to make hole bigger
ron kc0tdj

Re: New Facebook Group for D4D

W8NSI James
 

Great!  I do not use Farcebook either. This groups.io is just right.
--
73 de w8nsi jim

Re: d4d off frequency

ron mcmurray
 

the data sheet for the c1162 shows collector connected to the mounting hole, mine shows screw was shorting collector to ground.
ron, kc0tdj