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2014-05-13
Rackhandtag och skyddskåpa.
Produkter från GEMS PRODUCTS Tack Jan SM6CJJ för bilderna!
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2014-04-21
Artikel om kylning.
Augmentation of extended surfaces used to dissipate heat increases the overall effectiveness of a heat sink and increases the heat removed per unit volume. This amount of increase depends on the number of augmentations, air flow velocity and overall length of the cooling channels.
Läs artikeln här
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2014-04-18
Hi Lennart,
Thank-you for taking the time to respond to my email.
Here is a description that I prepared when I launched these replacement heat sinks.
Due to numerous posts in the American forums about digital modes causing the Elecraft KX3 to overheat, and due to unanswered requests for someone to take on the project of designing and manufacturing a good replacement heat sink that would protect the PA final transistors, I had an idea that a heavier heatsink would be a real asset. I am completely overwhelmed by the response.
I designed a heatsink based on the ideas of other discontinued heatsinks, and added my ideas borne out of 26 years in the radiant warm water heating industry.
The second question that most of my customers have asked has to do with the added weight. I am sorry I do not have the weight in grams but in pounds and ounces, the heat sink weighs approximately 8 oz.
The answer to the third question is, no, I will not offer a black anodizing finish for three reasons;
1. The radio is not anodized and so the color match is very poor
2. Anodizing aluminum is not an environmentally friendly process
3. The set up cost for small individual runs of anodizing is very expensive.
Included are pictures of matt glass beaded finish, white natural mill finish, and matte black powder coated finish. The most requested finish is matte black powder coating on all of the visible surfaces, with the contact surface left uncoated for better heat transfer.
The material that the heat sink is machined from is T6061 aluminum bar stock, fully machined in a CNC machine center with flood cooling.
The contact surface is ground for flatness and for fineness of finish to maximize the contact surface.The heat sink sole is 1/4” thick compared to the factory heat sink of 1/16”. The purpose of the heavy sole is to quickly extract the heat out of the PA chips and to a lesser degree out of the case. The fins are 1/2” tall and 1/8” thick. Their ends are radiused to prevent injury and damage to back packs or carrying cases. The purpose of the fins is to draw the heat out of the sole and provide more than 36 square inches of cooling surface for radiation and convection.
The features that set my design apart from the others that I have seen are as follows:
1. the most important feature I have usually have stock available for immediate shipment.
2. I have thickened the substrate that is in immediate contact with the exterior of the KX3 over the one that Elecraft supply with the rig. The increase is from 1/8” nominal to 1/4” nominal.
3. The 19 fins add approximately 36 square inches of surface area to help dissipate the PA heat.
4 I have made the end fins approximately 3/16” thick because in my experience the thinner fins found on off the shelf heat sink material is too easily damaged. I did not want to reduce the utility of the radio in its portable or back packing roles, especially during SOTA events where it might see a lot of ruck sack time. The thickness of the end fins will reduce the possibility of damage.
5. I included a 4-40 threaded accessory hole in each end fin. I chose the screw size as this is the size used by Elecraft for their case hardware, and it is standard among computer manufacturers so you should be able to scrounge some thumb screws locally. You might ask what benefit a threaded hole has? You can use the fixture to attach a lanyard with which to reduce the strain on the antenna connector while portable, you can make up a cover over the fins for transport, you can use the threaded hole to attach the rig to a base station stand (my intention as this is my base rig) or any other idea you might have. I through drilled the hole so that if you get dirt into the hole you can remove the heatsink and push the dirt out with a toothpick or small wire. You can also not use the attachment point at all if you choose not to.
I have also put together a quick installation kit consisting of the correct length screws and a driver to install them with.
Please edit my comments to suit the needs of the forum as you see fit.
For an unsolicited endorsement please read Ed W6ELA blog at http://www.aerodynes.fr/
or for Google users you can read about it at https://plus.google.com/u/0/communities/117833506194590431393
I can also recommend Ed KL7UW at http://www.kl7uw.com/KX3.htm
If I can be of further help, please do not hesitate to write. Yes I ship internationally.
Pricing is as follows:
KX3 heatsink in the white (milling machine finish- $60.00
KX3 heatsink in the matt (glass beaded finish)- $65.50
KX3 heatsink in the matte black powder coat- $93.00
Quick installation kit consisting of SS socket cap screws and a wrench– $5.50
Postage and packing for most of western Europe without tracking service is around – $25.00
PayPal adds 3%
Cheers, Fred, VE7FMN fsmeier@telus.net
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 2013-03-01 SA5BTB
Batterier i innerfickan.
I dag fick jag de två batterikassetter med plats för 10 st AA-batterier som jag vunnit på Tradera - inkl. 2 st dummies. Allt nytt och oanvänt. Perfekt att ha i fickan och koppla in vid behov.
10 st uppladdningsbara batterier ger 12 V och 8 st köpe-batterier ger 12 V. Batterierna på bilden lämnar 2600 mAh enligt specifikationerna.
Bara anslutningskabeln fattas.
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2013-01-02 SA5BTB
Jag har nu testat mitt nya Li-Fe-batteri och laddare. Intrycket är att de nya batterierna är helt fantastiska när det gäller prestanda. Mitt 4200 mAh väger 0,5 kg jämfört med mitt Biltema MC-bly-batteri på 7 Ah som väger nästan 3 kg. Jag påstår att det går att plocka ut fler mAh med Li-Fe-batteriet än blybatteriet. Detta huvudsakligen pga av att spänningen i blybatteriet kontinuerligt minskas - vilket inte sker med Li-Fe-batteriet som har en flack spänningskurva vilken dyker kraftigt på slutet. Ett stort tack till SM0FPR Mats som har ett förflutet inom RC-hobbyn och som har hjälp mig att förstå det här med Li-Po och Li-Fe-batterier.
Sammanfattning:
- Li-Fe (Lithium-Iron) är ett modernt batteri med ny teknik
- Ett laddat batteri kan lagras l ä n g e utan att det laddar ur sig
- Fulladddat på ca 75 minuter med 1C = 4,2 A (4200 mAh) som är normalvärdet. Kan snabbladdas.
- Märkningen = effektuttag. Alltså inte som Ni-MH som lämnar kvar 20-30 %
- Max strömuttag 30C (30 x 4,2 A) = 126 A i några sekunder
- Brinner vid kortslutning eller alltför stort effektuttag utöver specifikationerna
- Laddaren är knepig att ställa in med flera undermenyer
- För Li-Fe måste en laddare för just Li-Fe användas.
Laddare och batteri köpt från HobbyKing. Laddaren kom från HongKong (rek. brev 1 vecka) och batteriet från Tyskland (Schenker 1 vecka). 240 V EU-adapter måste användas till laddaren då den har en amerikansk kontakt. Jag har bytt ut batteriets och laddarens kontakter mot PowerPole-kontakter.
Det finns ett 8400 mAh 13,2 V Li-Fe-batteri som onekligen är intressant för andra andra riggar med större effekt.
Klicka på resp. bild för att komma till HobbyKings webb-shop.
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 2012-12-04 SA5BTB
Bra tryck i den lilla högtalaren från Elgiganten när jag testade i dag.
Länk:
LOGIK aktiv högtalare
Högtalaren drivs med 3 st AAA-batterier och har en till-från-knapp.Okänt hur länge batterierna räcker.
Det finns motsvarande produkter hos Clas Ohlsson och Dustin i olika prisklasser.
Ett bra tillbehör för portabelkörning om inte hörlurar används.
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2012-12-03 SA5BTB
I dag kom ett bordsställ till K3:an från Nifty Ham Accessories med posten. Ett mycket trevligt tillbehör som passar mig perfekt. Jag tror det även kan fungera bra ute i naturen.
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2012-11-19 SA5BTB
En dag i skogen ..
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