Date   
Re: Nice matching knob for inkits black case #ubitx #tuning-knob #parts

Ismo Väänänen OH2FTG
 

I have a similar one on my M0NKA mcHF and I really like the finger indent in it. Got it with the chinese mcHF case kit for my build.

Re: Band pass filter

Dave New
 

Toroids are self-shielding.

Axials need to be mounted at right angles to minimize coupling between them.  If you have three, you can mount them in the x, y, and z planes.

At this point, most folks just give up and use toroids. Laughing

73,

-- Dave, N8SBE

-------- Original Message --------
Subject: Re: [BITX20] Band pass filter
From: "Jack, W8TEE via Groups.Io" <jjpurdum@...>
Date: Thu, November 14, 2019 11:07 am
To: <BITX20@groups.io>

I'm a software guy, so probably shouldn't answer that. My gut says wound toroids are always better, but the axials worked fine for me. Some EE-type can give a better answer.

Jack, W8TEE

On Thursday, November 14, 2019, 10:39:43 AM EST, Doug W <dougwilner@...> wrote:


On Thu, Nov 14, 2019 at 08:15 AM, Jack, W8TEE wrote:
I built a QRP version for my 49-er that works quite well.
At QRP levels is there an advantage or disadvantage to using wound toriods versus radial inductors (or even SMD), especially on the receive side?
 
--
www.bitxmap.com

--
Jack, W8TEE

Re: Band pass filter

MadRadioModder
 

You might do a little investigating to see if there really is a loud station blocking your receiver before you invest in something you may not need.  The first thing I would try is just receiving off a long wire stuffed into the antenna port (NO TRANSMITTING!).  You’ll get a better understanding if the receiver is the problem that way.

 

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Preston
Sent: Thursday, November 14, 2019 10:22 AM
To: BITX20@groups.io
Subject: Re: [BITX20] Band pass filter

 

I am about 14 miles away.  I am in a densely populated area with a large apartment group next to our condo community, so I suspect there is probably a huge number of different electronic devices and there could be spurious emissions from them.

Preston

G. Preston Parker

5704 E Aire Libre Ave Unit 1025

Scottsdale, AZ 85254

preston.azcpapro@...

480 499-5427  866 459-5242

480 499-5761 Fax

http://azcpapro.com

Help us improve by taking a short survey http://www.azcpapro.com/client-survey.aspx

 

 

On Thu, Nov 14, 2019 at 7:44 AM Ken Held KF7DUR via Groups.Io <kf7dur=aol.com@groups.io> wrote:

The only AM broadcast transmitter in Scottsdale is located @ 64th st. & Thomas rd.
KAZG 1440AM 5,000 W day, 52 W night
Are you close to that location?


--

…_. _._

Re: Band pass filter

Preston
 

I am about 14 miles away.  I am in a densely populated area with a large apartment group next to our condo community, so I suspect there is probably a huge number of different electronic devices and there could be spurious emissions from them.

Preston

G. Preston Parker

5704 E Aire Libre Ave Unit 1025

Scottsdale, AZ 85254

preston.azcpapro@...

480 499-5427  866 459-5242

480 499-5761 Fax

http://azcpapro.com

Help us improve by taking a short survey http://www.azcpapro.com/client-survey.aspx



On Thu, Nov 14, 2019 at 7:44 AM Ken Held KF7DUR via Groups.Io <kf7dur=aol.com@groups.io> wrote:
The only AM broadcast transmitter in Scottsdale is located @ 64th st. & Thomas rd.
KAZG 1440AM 5,000 W day, 52 W night
Are you close to that location?

Re: Band pass filter

Jack, W8TEE
 

I'm a software guy, so probably shouldn't answer that. My gut says wound toroids are always better, but the axials worked fine for me. Some EE-type can give a better answer.

Jack, W8TEE

On Thursday, November 14, 2019, 10:39:43 AM EST, Doug W <dougwilner@...> wrote:


On Thu, Nov 14, 2019 at 08:15 AM, Jack, W8TEE wrote:
I built a QRP version for my 49-er that works quite well.
At QRP levels is there an advantage or disadvantage to using wound toriods versus radial inductors (or even SMD), especially on the receive side?
 
--
www.bitxmap.com

--
Jack, W8TEE

Re: Band pass filter

iz oos
 

For TX I would only use toroids or air wound coils. For RX you could use radial or SMD. The Q might be better with toroids, although.


Il 14/nov/2019 16:39, "Doug W" <dougwilner@...> ha scritto:
On Thu, Nov 14, 2019 at 08:15 AM, Jack, W8TEE wrote:
I built a QRP version for my 49-er that works quite well.
At QRP levels is there an advantage or disadvantage to using wound toriods versus radial inductors (or even SMD), especially on the receive side?
 
--
www.bitxmap.com

Re: Band pass filter

Doug W
 

On Thu, Nov 14, 2019 at 08:15 AM, Jack, W8TEE wrote:
I built a QRP version for my 49-er that works quite well.
At QRP levels is there an advantage or disadvantage to using wound toriods versus radial inductors (or even SMD), especially on the receive side?
 
--
www.bitxmap.com

Re: Band pass filter

David Forrest
 

Can you tune in the AM station (with either your MFJ1622 or a length of wire) to test the rest of the system?

Re: Band pass filter

Ken Held KF7DUR
 

The only AM broadcast transmitter in Scottsdale is located @ 64th st. & Thomas rd.
KAZG 1440AM 5,000 W day, 52 W night
Are you close to that location?

Re: Band pass filter

Martin Potter
 

Preston wrote :
"I am in a condo ... static ... periodic continuous tones"

It could also be RFI from a local source. If you can power the rig (receiver only) from a battery, put a whip antenna on it (or several feet of wire) and check the level of interference in your condo. Then go up to the roof and check, and out to the parking lot, and finally to the big park down the road. If there is much difference in the noise level between those different places ...
73,
... Martin VE3OAT

Re: Band pass filter

Jack, W8TEE
 

Preston:

There's an article (A Cheap and Easy BCI Filter”, CQ Magazine, August, 2016) that describes such a filter. I built a QRP version for my 49-er that works quite well. It cost be about $0.80 to build the QRP version (perf board works fine, of course):

Inline image

Inline image

Inline image


As you can see, the insertion loss is very small, but it knocks the slats out of any BCI interference.

Jack, W8TEE


On Wednesday, November 13, 2019, 11:29:00 PM EST, Preston <preston.azcpapro@...> wrote:


I am in a condo in Scottsdale, and have tried my new Ubitx on a MFJ 1622 apartment antenna and on a 40 meter half wave center fed dipole.  All I am getting is static on every band with some periodic continuous tones, although it worked in Wisconsin with a dipole.  The ARRL video on Youtube about the Ubitx says at the end, that there is an AM station within a mile that causes problems with the receiver.  They say to buy or build a band pass filter.  I am wondering if this is my problem.  Has anyone run into this?  If so, is there a brand and model that has worked for you?

--
Jack, W8TEE

Re: Nice matching knob for inkits black case #ubitx #tuning-knob #parts

howard winwood G4GPF
 

Same thing from China via eBay for £3.41 Inc free postage, just ordered one.


On Thu, 14 Nov 2019, 00:21 Robert Freeman, <michmasher@...> wrote:
Looks nice. Thanks for sharing. 

Robert NQ0T 

Re: Band pass filter

iz oos
 

Indeed, if the AM station is on mediumwave a BCI filter (just a highpass filter) is the solution. I have had a similar issue with a religious FM channel I heard spread over the 144mhz band. A highpass filter was enough. I hope you can solve it equally well. It also depends on how clean is their TX. But they might be legally compliant (-43db? from the fundamental) but not enough for you.


Il 14/nov/2019 05:29, "Preston" <preston.azcpapro@...> ha scritto:
I am in a condo in Scottsdale, and have tried my new Ubitx on a MFJ 1622 apartment antenna and on a 40 meter half wave center fed dipole.  All I am getting is static on every band with some periodic continuous tones, although it worked in Wisconsin with a dipole.  The ARRL video on Youtube about the Ubitx says at the end, that there is an AM station within a mile that causes problems with the receiver.  They say to buy or build a band pass filter.  I am wondering if this is my problem.  Has anyone run into this?  If so, is there a brand and model that has worked for you?

Re: Band pass filter

 

Preston,

 If it is indeed from a AM station I sell a BCI filter kit with instructions to install in the uBitx/Bitx40 radios for 5$

https://shop.kit-projects.com/index.php?route=product/product&path=59&product_id=118

73


--
David

 N8DAH
Kit-Projects.com

Shop is open!

Band pass filter

Preston
 

I am in a condo in Scottsdale, and have tried my new Ubitx on a MFJ 1622 apartment antenna and on a 40 meter half wave center fed dipole.  All I am getting is static on every band with some periodic continuous tones, although it worked in Wisconsin with a dipole.  The ARRL video on Youtube about the Ubitx says at the end, that there is an AM station within a mile that causes problems with the receiver.  They say to buy or build a band pass filter.  I am wondering if this is my problem.  Has anyone run into this?  If so, is there a brand and model that has worked for you?

Re: Nice matching knob for inkits black case #ubitx #tuning-knob #parts

Robert Freeman
 

Looks nice. Thanks for sharing. 

Robert NQ0T 

Nice matching knob for inkits black case #ubitx #tuning-knob #parts

Justin Phillips K5AXL
 

Found this guy on amazon, looks like it was made for this case. The inkits provided knob is functional, but wobbled a little bit on me, and I really missed a finger indent.

https://www.amazon.com/gp/product/B07CLXVCDM/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1 


Re: Using Vacuum Tube heathkit as Linear Amplifier for QRP

James Lynes
 

Yes it did. I read it last night. I believe the same info is on the qrp labs website in the qsx area.

James

Re: Using Vacuum Tube heathkit as Linear Amplifier for QRP

Bill Cromwell
 

Hi Richard,

I copied the whole thing from one of the ARRL Handbooks. I'm sure I can find it again. I will have a look. I do still have the T-R switch and maybe even the coupling capacitor. That cap is a "gimmick" made from about three inches of RG-58. Don't let the "gimmick" label throw you over. It is more than a little twisted pair as sometimes used in receiver circuits for regenerative feedback.

I built mine in an old TV tuner metal box. I don't know what they have in TV sets for a tuner these days but I think it is an SDR front-end. An Altoids tin (or something similar) would work. The transistor is a 40673 dual gate mosfet and is now just about unobtanium. Fortunately there are plentiful substitutes. You could also use a vacuum tube <grin>.

More later after I dig out the details. It is so easy that even *I* could do it.

73,

Bill KU8H

On 11/12/19 4:07 PM, Richard Spohn wrote:
Bill, do you have the schematic for the solid-state T/R switch, or
even better, do you still have that switch? I am keenly interested in
an all-electronic (no relays) T/R switch for QSK. Building one from
scratch may be slightly outside my skill set tho. -- Rich WB2GXM
--
bark less - wag more

Re: Using Vacuum Tube heathkit as Linear Amplifier for QRP

Jack, W8TEE
 

Didn't Hans QSX talk at FDIM and reprinted in QRPQ (October issue??) discuss a "relayless" TR switch?

Jack, W8TEE

On Tuesday, November 12, 2019, 4:08:07 PM EST, Richard Spohn <wb2gxm@...> wrote:


Bill, do you have the schematic for the solid-state T/R switch, or
even better, do you still have that switch?  I am keenly interested in
an all-electronic (no relays) T/R switch for QSK.  Building one from
scratch may be slightly outside my skill set tho. -- Rich WB2GXM

On 11/10/19, Bill Cromwell <wrcromwell@...> wrote:
> Hi,
>
> In the 80s I built boots for an Ten Tec Argonaut 509 using the carcass
> of a Heathkit DX-35. There is no receive circuitry involved. I biased
> the single 6146 for class AB1 operation. I built a solid state T-R
> antenna switch to keep the QSK feature of the 509. It served me for a
> several years and then the 509 moved to a new home. The remains of the
> DX-35 also went to another ham.
>
> I have the CW portion of a Heathkit DX-100 down for overhaul. The AM
> phone parts were all gone when I got the DX-100. I am going to dpo the
> mods to include the linear operation in phone mode to amplify SSB
> signals and keep the class C operation for it's CW operation - ala the
> Apache (TX-1). Grid block keying has already been part of this
> particular DX-100.
>
> Sometimes QRP is just not enough.
>
> 73,
>
> Bill  KU8H
>
> On 11/10/19 7:35 AM, Don Richards wrote:
>> Hi Gordon
>> I ran across this a while back but never tried it.
>>
>> https://www.google.com/url?sa=t&source=web&rct=j&url=https://frrl.files.wordpress.com/2008/09/hotwaterforthek2.pdf&ved=2ahUKEwjwzsTQ09_lAhWsmuAKHQ1MCyYQFjACegQIARAB&usg=AOvVaw1PdjqVxSUEw-wayoqwuZyO
>>
>> 73 Donve3ids
>
> --
> bark less - wag more
>
>
>
>




--
Jack, W8TEE