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Date
Re: Harmonics and Relay Replacement
Jim, I've looked over that spec sheet and the only thing that tells me is that they are "Signal Relays" have gold plated contacts (all good but not unique to Axicom) ...........and the ones you
By Kees T · #60602 ·
Re: Simpler spur fix
1206 version is available at Digikey 535-11689-1-ND Cheers, Jim W0CHL
By Jim Reagan · #60600 ·
Re: High Frequency Choke for Bitx40
I think you are looking for something like this. http://toroids.info/FT114-43.php ( http://toroids.info/FT82-43.php ) For fun use the calculator on that page, enter?160 or higher bands in MHz ?along
By tdelozie · #60598 ·
Re: Recommended fixes on ubitx.net
Mr Woods, I can't thank you enough for Ubitx.net.? It's very difficult to keep up with everything here in the groups...or find previous postings.? It's very helpfull to have it all neatly summarized
By davedt1e@... · #60597 ·
Re: Harmonics and Relay Replacement
I use pliers and break the component to be removed. Once it is broken apart you can focus on removing one pin at a time. No overheating the board or pads. There is not much thermal mass to draw away
By Mike Short <ai4ns.mike@...> · #60596 ·
High Frequency Choke for Bitx40
Hello I'm planning to do the filtering mods for the Bitx40 described here. https://ubitx.net/2018/07/06/belt-and-braces-filtering-of-a-bitx40-power-supply/ The only question I have is what sort of
By craigmclean@... · #60595 ·
Re: Harmonics and Relay Replacement
See the link I posted from the vender, download and study the data sheet yourself.
By Jim Sheldon · #60594 ·
Re: Harmonics and Relay Replacement
I really suspect they were really careful with the dielectric properties of all the case and internal insulating material as well as coil wire routing as far away from the switching contacts as
By Jim Sheldon · #60593 ·
Re: Harmonics and Relay Replacement
Jim, Yes, I've seen that posted by you before......but what did they do specifically for RF use ? some spacings ? shielding ? coil core material ? base dielectric ? housing dielectric ? I also see
By Kees T · #60592 ·
Re: Harmonics and Relay Replacement
Kees, The Axicom relays were designed specifically for RF use and were made with RF isolation in mind where the original relays have almost no RF isolation between contacts, armature & coil because
By Jim Sheldon · #60589 ·
Re: Harmonics and Relay Replacement
I think it's great to discover, but I would still like to see WHY the Axicom relays fix the problem and some data plots with and without. There has to be a reason other than the coil being on top of
By Kees T · #60588 ·
Re: Simpler spur fix
Do you think mounting the original toroids on the bottom of the board would work?
By Jack Zielke · #60587 ·
Re: Simpler spur fix
Been looking around for the 1210 680nh inductors?and cannot find a source yet. I noticed some suppliers only sell in very large quantities like 2000. So has anyone found a source yet or if so would
By mark bodlovich · #60586 ·
Re: Harmonics and Relay Replacement
Top IMO. Bottom actually degraded things on MY board. Probably need a few more people to test tis before a cull consensus can be reached. Jim
By Jim Sheldon · #60585 ·
Re: Harmonics and Relay Replacement
So, is the relay mod a sure thing? I have put off ordering the relays until somebody says it definitely works. I jumped on the 45Mhz filter bandwagon and have them all installed and working on two
By Joel Caulkins/N6ALT · #60584 ·
Recommended fixes on ubitx.net
With two simple new fixes available to address the spectral purity issues associated with the uBITx, I have been busy updating the www.ubitx.net website this morning.? This includes an update to the
By Mike Woods · #60583 ·
Re: Harmonics and Relay Replacement
Jim Would you be able to take a photo of a uBITx with the new Axicom relays in place?? It would be nice to be able to show this on ubitx.net.?? I have ordered relays from Hong Kong, but they will
By Mike Woods · #60582 ·
Re: Harmonics and Relay Replacement
Jim: I have built everything in my shack including an Elecraft K2 (I was a beta tester for the 100-watt linear amp), auto-tuner, and other smaller projects. So, I am fairly comfortable, but putting
By David Posthuma · #60581 ·
Re: Homebrew from scratch #ubitx
Hi Peter, Our radio club are so impressed we have 12 members who are going to build the the uBITZ using the through hole system. I'm sourcing components and PCB's using the gerber files. However the
By G8HAV · #60580 ·
Re: Harmonics and Relay Replacement
Solder braid or a precision vacuum desoldering tool should be used IMO. If you have a Hakko or Pace desoldering station with heated tip vacuum tool this is best. I have a powerful spring loaded
By Jim Sheldon · #60579 ·