Date   
Microphone for 40mtr transceiver KN-7QA

JOHN CRONHELM
 

Hi All,
Does anyone know if you can use a MFJ 290 mic with the KN-7QA Kit transceiver.
Thanks,
John vo1 jcc

Re: Microphone for 40mtr transceiver KN-7QA

n7rgw
 

If you have the wiring for the Microphone, you can always rewire the KN-Q7A connector to mate with it.

Re: Microphone for 40mtr transceiver KN-7QA

 

Larry,
I still have the rig I got from you and the early MIC.
I saw many post for a MIC with improvements on it but I still use mine and check into the early morning nets.
Just wanted to know if the newer MIC is still around.
BOB
AF2DX
 
 

In a message dated 4/8/2016 10:22:05 A.M. Pacific Daylight Time, CHINA_QRP@... writes:
If you have the wiring for the Microphone, you can always rewire the KN-Q7A connector to mate with it.
 

Microphone

JOHN CRONHELM
 

I notice they suggest an electret microphone for the KN-7. 40 mtr. Kit. Has anyone had experience of using a dynamic microphone appropriately wired.
Many thanks,
John,vo1jcc.

Re: Microphone

qrpjl1kra
 

As you see the schematic of KN-Q7A, 
it does not have any amplifier in front of a modulator NE602.
This means the mic output needs higher output level up to 1V-pp. 
Dynamic mic need an additional amplifier.
Otherwise you will see low RF output power.

The best recommendation is the original stock mic supplied by CRkits.

Junichi JL1KRA, Yokohama

Re: Microphone

JOHN CRONHELM
 

Cannot find any reference to the stock microphone for KN-Q7A. only speaker mic. mentioned. I wonder what the price is.  Does it have a model name or number.?


On Apr 9, 2016, at 6:39 AM, mx6s@... [CHINA_QRP] <CHINA_QRP@...> wrote:

 

As you see the schematic of KN-Q7A, 

it does not have any amplifier in front of a modulator NE602.
This means the mic output needs higher output level up to 1V-pp. 
Dynamic mic need an additional amplifier.
Otherwise you will see low RF output power.

The best recommendation is the original stock mic supplied by CRkits.

Junichi JL1KRA, Yokohama

Re: Microphone

Dan Pflugrath
 

With the stock speaker mic out of stock I rewired an $8 EBay Boefeng speaker mic plus the connector and it seems to work well.  I added a 50K miniature trim pot inside so I could adjust the mic output to not overdrive the KN-Q7A.
Dan

Re: Microphone

JOHN CRONHELM
 

Dan, 
Very many thanks for that information. Didn't realize the speaker mike was the stock one. Thought the stock one was a pure microphone.
John.


On Apr 9, 2016, at 1:27 PM, dpflugrath@... [CHINA_QRP] <CHINA_QRP@...> wrote:

 

With the stock speaker mic out of stock I rewired an $8 EBay Boefeng speaker mic plus the connector and it seems to work well.  I added a 50K miniature trim pot inside so I could adjust the mic output to not overdrive the KN-Q7A.
Dan

Re: Microphone

JOHN CRONHELM
 

I am not sure how you figured out which wire went where particularly as there was a mixture of mic and speaker wires. Did you cut the wire above the connector or did you leave the connector attached. How did you connect the male connectors to the rig. Did you drill the front panel and put in two female miniature connectors?
Many thanks again.
John.

Re: Microphone

Dan Pflugrath
 

Re: Microphone

JOHN CRONHELM
 

Hi Dan,
Do you have the color coding of the wires from the speaker mic that you attached the 6 pair cable to ? Or did you trace continuity to the connector?  I have the pin out for the connector.
Many thanks,
John.

On Apr 9, 2016, at 9:14 PM, 'dpflugrath@...' dpflugrath@... [CHINA_QRP] <CHINA_QRP@...> wrote:

 

I replaced the coiled mic cable with a length of 6 pair cable.
Dan

Please note: message attached

From: "johncronhelm@... [CHINA_QRP]" <CHINA_QRP@...>
To: <CHINA_QRP@...>
Subject: [CHINA_QRP] Re: Microphone
Date: 09 Apr 2016 14:54:25 -0700

__________________________________________________________
Wall Street Daily
Peter Schiff: China Just Armed its Financial Missile
http://thirdpartyoffers.juno.com/TGL3131/5709941db6744141d7456st02duc

Re: Microphone

Dan Pflugrath
 

I used a 6 wire cable replacing the original 5 wire cable to connect the speaker (2), microphone (2) and PTT (2) separately with a common ground point at the KN-Q7A per the schematic.

 

I had to cut a trace in the speakermic to isolate the PTT ground from the microphone.  In the original speakermic the PTT switch ties the PTT and microphone grounds together and this caused feedback in the transceiver thus the extra 6th wire.  I cut the trace near the PTT switch and one of the PTT lines connected there and the other was connected to the PTT solder tab.

 

The output of the microphone was too low so I removed the resistor that was across the electret mic and put a small 10K trim pot across the mic solder pads in the cavity where the wires enter the speakermic housing.  I adjusted the pot so the transmitter would not be overdriven.

 

As for color coding I connected the labeled solder pads in the speaker mic to the 8 pin connector per the KN-Q7A scheematic.

 

If you want a visual I can open it up a provide you with a picture.

 

Dan

 

From: CHINA_QRP@... [mailto:CHINA_QRP@...]
Sent: Tuesday, April 12, 2016 3:24 PM
To: CHINA_QRP@...
Subject: Re: [CHINA_QRP] Re: Microphone

 

 

Hi Dan,

Do you have the color coding of the wires from the speaker mic that you attached the 6 pair cable to ? Or did you trace continuity to the connector?  I have the pin out for the connector.

Many thanks,
John.


On Apr 9, 2016, at 9:14 PM, 'dpflugrath@...' dpflugrath@... [CHINA_QRP] <CHINA_QRP@...> wrote:

 

I replaced the coiled mic cable with a length of 6 pair cable.
Dan

Please note: message attached

From: "johncronhelm@... [CHINA_QRP]" <CHINA_QRP@...>
To: <CHINA_QRP@...>
Subject: [CHINA_QRP] Re: Microphone
Date: 09 Apr 2016 14:54:25 -0700

__________________________________________________________
Wall Street Daily
Peter Schiff: China Just Armed its Financial Missile
http://thirdpartyoffers.juno.com/TGL3131/5709941db6744141d7456st02duc



Re: Microphone

JOHN CRONHELM
 

Thank you Dan,
A visual would be very useful, when you get a chance to do that. I am waiting for a Baofeng Spk. Mic from eBay.
John.


On Apr 13, 2016, at 12:05 AM, 'Dan Pflugrath' dpflugrath@... [CHINA_QRP] <CHINA_QRP@...> wrote:

 

I used a 6 wire cable replacing the original 5 wire cable to connect the speaker (2), microphone (2) and PTT (2) separately with a common ground point at the KN-Q7A per the schematic.

 

I had to cut a trace in the speakermic to isolate the PTT ground from the microphone.  In the original speakermic the PTT switch ties the PTT and microphone grounds together and this caused feedback in the transceiver thus the extra 6th wire.  I cut the trace near the PTT switch and one of the PTT lines connected there and the other was connected to the PTT solder tab.

 

The output of the microphone was too low so I removed the resistor that was across the electret mic and put a small 10K trim pot across the mic solder pads in the cavity where the wires enter the speakermic housing.  I adjusted the pot so the transmitter would not be overdriven.

 

As for color coding I connected the labeled solder pads in the speaker mic to the 8 pin connector per the KN-Q7A scheematic.

 

If you want a visual I can open it up a provide you with a picture.

 

Dan

 

From: CHINA_QRP@... [mailto:CHINA_QRP@...]
Sent: Tuesday, April 12, 2016 3:24 PM
To: CHINA_QRP@...
Subject: Re: [CHINA_QRP] Re: Microphone

 

 

Hi Dan,

Do you have the color coding of the wires from the speaker mic that you attached the 6 pair cable to ? Or did you trace continuity to the connector?  I have the pin out for the connector.

Many thanks,
John.


On Apr 9, 2016, at 9:14 PM, 'dpflugrath@...' dpflugrath@... [CHINA_QRP] <CHINA_QRP@...> wrote:

 

I replaced the coiled mic cable with a length of 6 pair cable.
Dan

Please note: message attached

From: "johncronhelm@... [CHINA_QRP]" <CHINA_QRP@...>
To: <CHINA_QRP@...>
Subject: [CHINA_QRP] Re: Microphone
Date: 09 Apr 2016 14:54:25 -0700

__________________________________________________________
Wall Street Daily
Peter Schiff: China Just Armed its Financial Missile
http://thirdpartyoffers.juno.com/TGL3131/5709941db6744141d7456st02duc



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Re: Microphone

Dan Pflugrath
 

See pictures attached.  Not sure if a Baefeng is wired the same but should be similar.  The cable I used is a thin wire gage Cat5 cable.  I used 6 of the 8 wires.  You do need to isolate the ground side of the PTT switch and run one of the PTT wires up to the switch. I did not have enough signal from the Mic so I removed the resistor across it and added the pot to be able to adjust the mic output level.  I tied all the grounds together at the connector. 

If you ohm out the Baefeng PTT you should find the PPT connects the Mic ground to the speaker ground.  This arrangement caused feedback in the KN7-Q7A so I went to the separate PTT lines.

Dan KA7GPP. 

Re: Microphone

JOHN CRONHELM
 

Dan, very many thanks for your pictures and explanation of wiring.
John.

Engineering Change Notice for CRK-10A kit

Adam Rong
 

Folks,

Starting from today, you might find red trimmer capacitors in your CRK-10A kit. It means they are 5~20 pF instead of 10~50 pF (brown ones). The change is triggered by the new batch crystals. They now have 20 pF load capacitor instead of 30 pF. If we don’t do this change, customers might find it difficult to tune either RX or TX frequency high enough to the specified value printed on the crystals.

If you find the problem in your kit, feel free to contact your seller for the replacement parts. Sorry for the inconvenience it might have caused.

Thanks,
Adam

rockbending_6 CW board

Todd Brooks
 

Does anyone out there have the schematic or installation/build manual for the rockbending_6 kit from taobao.com/mykits? Very close to the attached photo. I bought the board and they did not send a manual or schematic. I emailed them and they told me they did not have it. Go figure. Someone please help.

KN-Q7A review published

Adam Rong
 

Folks,

James Hannibal, KH2SR just published a review in his Examiner column for his 20 meter version KN-Q7A. Here is the link to the informative article:

Besides direct purchase from crkits.com, you also can check with your local distributors in US, Europe and Japan.

Thanks,
Adam

Re: rockbending_6 CW board

mlifgr@...
 

Rockbending_6

Todd Brooks
 

Does anyone out there have the schematic or installation/build manual for the rockbending_6 kit from taobao.com/mykits? Very close to the attached photo. I bought the board and they did not send a manual or schematic. I emailed them and they told me they did not have it. Go figure. Someone please help.