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more questions

 

Hi everyone,

I just go my case from Sunil and I'm mapping things out in my melon. Question... I would like to run a bci filter and an rf gain (5k pot) control. Both will be on the rx line. Should I run these in series or parallel after I cut the trace?

If series, bci or rf gain closer to k1?

Thanks again!
 

Sam

I would evaluate your uBITX to see if you need either feature.? See if you have any BCI interference, and if you did experience some I would be so tempted to check performance connected to batter y to insure leakage isn't getting into your power supply.? (I have neither feature in my uBITX - but I did add a VK3YE based AGC).?

If you want both BCI filter and RF gain control, it really does not matter much which order.? Perhaps a slight nudge to putting the filter first, in unlikely event the RF gain control generates spurious from the BC energy.? I imagine you saw the ND6T suggestion in installing the RF gain control.?

I had quite a snipe hunt with assembly into that case.? Visit ubitx.com for suggestions on using that case, there was a nice video there I wish I had watched before assembly of mine,? Those in my club build may still be laughing at my challenges on this.? Be patient and enjoy the build.?

Curt
 

My bci is wicked. I live a mile away from AM broadcast towers.

Was contemplating what to do with the unused?RF/Mic gain control. Might bring the rv1 pot out for reducing input power for the linear. I went thru quite a bit of the parts and it looks like it will be a mix/match between both kits. Sunil spoke of a mic amp kit coming soon. I have one, but I want to keep this nice and clean.
Jack Purdum
 

We've built 7 ?BITX's and all had some form of BCI, probably because of where I live. Al (AC8GY) also had BCI issues, but only when he used his vertical antenna. The EFHW was fine. I killed mine with an $0.87 BCI filter:

Inline image

which can be made with axial or toroid inductors (T50-6 toroids). I put the axial version in my 49-er:

Inline image
Insertion loss is minimal:

Inline image

Jack, W8TEE


On Friday, March 29, 2019, 12:12:22 PM EDT, Curt via Groups.Io <wb8yyy@...> wrote:


Sam

I would evaluate your uBITX to see if you need either feature.? See if you have any BCI interference, and if you did experience some I would be so tempted to check performance connected to batter y to insure leakage isn't getting into your power supply.? (I have neither feature in my uBITX - but I did add a VK3YE based AGC).?

If you want both BCI filter and RF gain control, it really does not matter much which order.? Perhaps a slight nudge to putting the filter first, in unlikely event the RF gain control generates spurious from the BC energy.? I imagine you saw the ND6T suggestion in installing the RF gain control.?

I had quite a snipe hunt with assembly into that case.? Visit ubitx.com for suggestions on using that case, there was a nice video there I wish I had watched before assembly of mine,? Those in my club build may still be laughing at my challenges on this.? Be patient and enjoy the build.?

Curt

 

Hi Jack,

I don't have that kind of scratch laying around! Looks good...I'll definitely make one if this one sucks.
Laurence Oberman
 

Sam it DOES NOT suck :) It works very very well.
Its just not meant for transmit, Jack's can take the transmit.

On Fri, Mar 29, 2019 at 12:37 PM Sam Tedesco <stedesco619@...> wrote:

Hi Jack,

I don't have that kind of scratch laying around! Looks good...I'll definitely make one if this one sucks.
 

No need for tx. I like this Distill board cause it's clean ...plus, I have zero inductors in the arsenal.
 

Sam

Take small steps to see what works. The inductors from Jack's design can be found on ebay, a hamfest, or via W8DIZ toroids.

Curt
Jack Purdum
 

Also, Tayda electronics () sells axial inductors like those shown in my photo for $0.09 each. Also, they have a distribution warehouse in Livingston, CO, so parts arrive fairly quickly.


Jack, W8TEE



On Friday, March 29, 2019, 3:59:43 PM EDT, Curt via Groups.Io <wb8yyy@...> wrote:


Sam

Take small steps to see what works. The inductors from Jack's design can be found on ebay, a hamfest, or via W8DIZ toroids.

Curt

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