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Ewald Böhm <ewvesb@gilltaylor.ca>: Sep 07 06:15AM How can we tell from an HP WiFi card spec whether the NIC is 2.4GHz or 5GHz, or both?   I'm trying to help my sister buy an HP laptop on the web.   My problem is that I contacted HP Support (via their chat mechanism) because USA phone support is not open now, and technical support isn't open tomorrow.   All I want to know is HOW to tell if a WiFi card has both 2.4GHz and 5GHz.   For $300 at Costco, plus $30 for shipping, this seems to be a decent 15.6-inch display laptop: http://www.costco.com/HP-15z-Laptop-|-AMD-E1-|-Windows-10.product.100222779.html   The main drawback from that Costco offering is that the WiFi isn't "ac", there's no mention of bluetooth, and the laptop doesn't come with Office 2013.   But, we can fix that at the HP web site.   If we go to the HP site to buy it, we can customize it to add what Costco doesn't have (and get free shipping). http://store.hp.com/us/en/pdp/Laptops/hp-pavilion-15z-laptop-m7d88av-1#!&TabName=specs   0. We start with the HP price of $350 which comes with twice as much memory as Costco's (4GB -> 8GB) plus free shipping (worth $30), so it's only $20 more than the Costco price. 1. We add the Microsoft Office Home & Student 2013 from HP for an extra $140 (either boxed, or already installed - I suggest they get the box for easier re-use later). https://store.hp.com/webapp/wcs/stores/servlet/CTOAddonsView?partNumber=QM4342 2. We add a WiFi "ac" card from HP for an extra $30 but is it dual band, 2.4GHz and 5GHz or not? 3. We add an extra wireless mouse and keyboard (no wires!) for $30 (because my sis wants that). https://store.hp.com/webapp/wcs/stores/servlet/CTOAddonsView?partNumber=LV290AA%23ABA The resulting price is $550 + tax (free shipping).   For that price, I see she gets a good laptop, but I chatted for half an hour with the HP sales chat people and they couldn't confirm if this 802.11 n/ac laptop has both 2.4GHz and 5GHz or if it only has one of those two frequencies.   HP chat sent me this URL but it just confirms that both "ac" and "n" don't have to be dual band; either one can be a single band. Also, it confirmed the 1x1 or 2x2 or 4x4 just means the number of dedicated data transmit and data receive antennas, which says absolutely nothing about the frequency. http://www.intel.com/content/dam/www/public/us/en/documents/pdf/next-gen-80211ac-wifi-for-dummies.pdf   My question is ... How can we tell from the HP WiFi card spec whether the NIC is 2.4GHz or 5GHz, or both?

Jeff Liebermann <jeffl@cruzio.com>: Sep 07 12:42AM -0700 On Mon, 7 Sep 2015 06:15:37 +0000 (UTC), Ewald Böhm   >How can we tell from an HP WiFi card spec whether the NIC is 2.4GHz or 5GHz, >or both?   >All I want to know is HOW to tell if a WiFi card has both 2.4GHz and 5GHz.   Looks at the specs. If it says 802.11 followed by: b/g = 2.4 GHz only b/g/n = 2.4 GHz only a = 5 GHz only a/b/g/n = 2.4 and 5 GHz The key is the "a" as in 802.11a, which is 5 GHz only.   >For $300 at Costco, plus $30 for shipping, this seems to be a decent 15.6-inch >display laptop: >http://www.costco.com/HP-15z-Laptop-|-AMD-E1-|-Windows-10.product.100222779.html   Broken link. Try: <http://reviews.costco.com/2070/100085182/hewlett-packard-hp-envy-15z-laptop-amd-quad-core-a10-backlit-keyboard-reviews/reviews.htm> which says: 802.11b/g/n WLAN which is 2.4 GHz only. You might want to read the reviews.   >The main drawback from that Costco offering is that the WiFi isn't "ac", there's >no mention of bluetooth, and the laptop doesn't come with Office 2013.   A BlueGoof dongle can be plugged into the a USB port. <http://www.ebay.com/itm/321216764033> <http://www.ebay.com/itm/171217973745> Buy a few spares as I've been shipped defective receivers.   Office 2013 is usually extra. If you must have Microsoft Office, look at Office 365 or the various Office Mutations available. Or, use free open source software such as Libre Office or Open Office. There are also Office alternatives: <http://www.informationweek.com/software/productivity-collaboration-apps/8-microsoft-office-alternatives/d/d-id/1320386> <http://www.digitaltrends.com/computing/best-microsoft-office-alternatives/> <http://www.pcworld.com/article/2010005/5-free-open-source-alternatives-to-microsoft-office.html>   Still nym shifting?   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

gyro_john <john.wetzel@shaw.ca>: Sep 06 07:46PM -0700 On Saturday, May 2, 2015 at 8:03:23 AM UTC-6, Arfa Daily wrote:   > I've never come across any function like this. What sort of TTL signal can > you 'translate' what is essentially a multi-level analogue signal into ?   > Arfa   Computer monitor / character generator stuff.

"Tim Williams" <tmoranwms@charter.net>: Sep 06 01:03PM -0500 "DaveC" <not@home.cow> wrote in message news:0001HW.1B9BFB3100248A5811E4F83CF@news.eternal-september.org... > Dead. Other with identical markings measure as NPN. What else to determine > from measurements?   Find a modest to high voltage supply, add a large series resistor (10k-100k?), and measure the reverse breakdown.   Wire it as a common emitter amplifier, not really to amplify but just to check bias. Play with base resistors until you get the edge of saturation for some collector current. Then double the collector current and do it again. That'll more or less let you plot hFE(Ic). Where it drops by half or so is near Ic(max).   Now you know Vebo, Vcbo, hFE and Ic(max). Vebo is generally less than 5V for RF parts, so you'll likely have a high fT in that case. You can set it up with a square wave input to measure t_r, t_f, t_stg etc. if you like.   Tim   -- Seven Transistor Labs Electrical Engineering Consultation Website: http://seventransistorlabs.com

Mark Lloyd <not@mail.invalid>: Sep 06 11:55AM -0500 On 09/05/2015 09:50 PM, Ewald Böhm wrote:   >> WPA2/PSK is one thing that is needed. Another is a better ESSID.   > You need both. > One without the other is worthless.   Yes, both are better. I was never recommending only one, even though that would be far from worthless.   -- 110 days until the winter celebration (Friday December 25, 2015 for 1 day).   Mark Lloyd http://notstupid.us/   "If I see a professing vegetarian eating meat, it is no hypocrisy for me to point out his inconsistency even though I personally do not subscribe to the principles of vegetarianism."

"Ian Field" <gangprobing.alien@ntlworld.com>: Sep 06 05:50PM +0100 "Bruce Esquibel" <bje@ripco.com> wrote in message news:mshauo$k4q$1@remote5bge0.ripco.com... > it wouldn't let the machine power up either, but at least there was a > "dew" > light, usually yellow saying why.   Last VCR I returned either didn't have a dew sensor, or it didn't work.   It was a sony and the LP function didn't work on the longer tapes, just as I returned it to the store I remembered I'd left a tape in it. The suggestion to plug it in and hit eject resulted in a tightly bound head drum.   Having been carried outdoors then taken into a busy store with lots of humidity, it developed an abundance of condensation.   On the bright side - I didn't have any difficulty persuading the store it was defective.

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