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I have read a lot about loops and the formulas for calculating a loop for the lowest band you would like to operate. I have a situation where I a large area to create a loop and wanted some input

Thanks Everett. Yes if you need the same footprint as the 2SC5551 use the BFU590QX. My PCB's used the larger BFU590GX. Of course both work exactly the same. Just watch out what package you need.

Tom, You need to clarify that that is BFU590QX.. Everett? Sent from the all new AOL app for iOS

I found that the BFU590's work well in the LZ1AQ circuit. The bias might need to be tweaked slightly to get the lowest IMD if you live in a local BCB area. But once set they seem work as well as the

I was poking around on Thingverse and found a bunch of printables to help mount loops on the LZ1AQ active antenna box. Some cool stuff here. https://www.thingiverse.com/search?q=Lz1aq&page=1 Also

Vce, can be a major problem when the load is a transformer with almost zero resistance, and very little if any resistance in the emitter path to ground. Regards, Martin

Hi Mike, maybe these Application Notes are

Hi John, Yes. 2SC3357 is a good device. I have a reel of RF class. Please email me your mailing address,? I will give you as you need. As Fred said, it is more fragile than the 2SC5551AF and

I just finished putting together an Improved LZ1AQ Loop amplifier that I am offering in several different configurations. One of them is with coax to offer a complete loop. Also this amp could be used

I have a W6LVP on a Yaesu rotator but keep my CC Active HF v4 stationary on a fence post, positioned for lowest noise. I like playing around with diversity using both. Experimenting is half the fun.

The NE46134 / 2SC3357 is an excellent RF-Transistor. These meanwhile obsolete transistors are widely used in the RF Stages of Elecraft radios, as for example in the K3. A very similar but newer

I use an Aziloop located 400ft away from house at the bottom of a field in the clear and it works really well 1-10MHz, Sharp nulls in loop mode from VLF to HF, but in K9AY mode it is limited by the

Thanks Hisami, the 4703 certainly looks promising. It is available over here from LittleDiode, a UK supplier on Ebay, but rather expensive so I will give that one a miss. However, I have just found

Hi John I have some genuine National Semiconductor 2222A's? I am happy to send you some if you are interested in wanting some reference units. Let me know, the postage is on me. Craig

Hi Mike , Thanks for the advice. I will take care. The RSP Duo SDR I own has a 4.7V Bias-T. It looks just fine. 73, Hisami 7L4IOU

Hi Martin, Thank you for pointing this out, I will check it. According to the store's web, they have a significant inventory. currently 790 bags, i.e. 3160 pieces. I will buy some. 73, Hisami

Parameters look good. 2.5dB noise figure is good enough for HF. The only issue is Vce max 12V. This means it is risky to use it in the most popular designs like LZ1AQ. The design should be modified to

Hi Hisami, It may be worth trying some, but they seem to be listed as being obsolete, and don't appear to be widely available. Regards, Martin

It's not much different from a Wellbrook and rotator in terms of cost, but it is much more sophisticated, and a lot of thought has gone into it's design. I think if you are interested in the LF

Hi All, I was browsing for BJTs at Parts Shop in Akihabara. There, a nice transistor called 2SC4703-NE46234? is available at a low