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#1
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On 3/17/2012 10:06 PM, DrTeeth wrote:
Hi guys, Could you tell me what sort of wattage a soldering iron needs to have to cope with soldering co-ax into PL509s? I've never had luck with irons: I use a soldering gun. The Weller 140 watt model works OK. If you have the choice, I recommend switching to BNC or N connectors: they're much easier to assemble, and have far less loss. Bill, W1AC -- Bill Horne (Remove QRM from my address to write to me directly) |
#2
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On Mon, 19 Mar 2012 12:10:20 EDT, just as I was about to take a herb,
Bill Horne disturbed my reverie and wrote: I've never had luck with irons: I use a soldering gun. The Weller 140 watt model works OK. Thanks Bill, it is on my shopping list ;-). -- Cheers DrT ______________________________ We may not be able to prevent the stormy times in our lives; but we can always choose to dance in the puddles (Jewish proverb). |
#3
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On Mar 19, 11:10 am, Bill Horne wrote:
If you have the choice, I recommend switching to BNC or N connectors: they're much easier to assemble, and have far less loss. Hadn't thought about the loss perspective. I don't care for the PL-259's tendency to not make good connection on the pin after a few insert cycles and I hear that N connectors are a bit better. But I've not considered BNC, at least for HF work. I use them on VHF/UHF but my power levels are well under 50W and SWR's are all fairly reasonable (under 3:1). Am I safe using BNC at 100W on HF with SWR's in the 5:1 range? What is the breakdown voltage of a BNC connector? -= Bob =- |
#4
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On Tue, 20 Mar 2012 00:15:44 EDT, just as I was about to take a herb,
KC4UAI disturbed my reverie and wrote: But I've not considered BNC, at least for HF work. Though it may be an impure thought, but don't HF commercial rigs all have SO 259s? Are adaptors available? -- Cheers DrT ______________________________ We may not be able to prevent the stormy times in our lives; but we can always choose to dance in the puddles (Jewish proverb). |
#5
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Yes - but the adapters are quite lossy.
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#6
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In article Channel Jumper writes:
DrTeeth;788676 Wrote: But I've not considered BNC, at least for HF work. Though it may be an impure thought, but don't HF commercial rigs all have SO 259s? Are adapters available? -- Cheers Yes - but the adapters are quite lossy. Actually, I have not found significant loss in any of these adapters I have used. If they had much loss, they would get warm (or hot) when transmitting, and none I have used do. Alan |
#7
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#8
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-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1 In writes: On Mon, 26 Mar 2012 01:45:59 EDT, (Alan) wrote: In article Channel Jumper writes: DrTeeth;788676 Wrote: But I've not considered BNC, at least for HF work. Though it may be an impure thought, but don't HF commercial rigs all have SO 259s? Are adapters available? -- Cheers Yes - but the adapters are quite lossy. Actually, I have not found significant loss in any of these adapters I have used. If they had much loss, they would get warm (or hot) when transmitting, and none I have used do. Alan I agree with Alan. The adapters are not lossy. I use them frequently to connect the outputs of my handhelds (BNC, SMA) to mag-mount antennas (UHF connector). They work fine. Good output signal and good reception. No heat generated. Dick Grady, AC7EL To respond to me privately, email to: My Call at My Call dot org Reading around on the subject, it seems that there are different kinds of losses in connectors and transmission lines, and not all of them will cause heating at the junction or interval where the loss occurs. Some knowledgeable amateurs have noted that we sometimes confuse transmission losses and insertion losses. Transmission loss, either Ohmic resistance or dielectric, will be dissipative, and directly heat the transmission line where the losses occur. Insertion loss, such as from impedance mismatch, results in power being reflected. Even impedance-matched connector conversions (50 Ohm to 50 Ohm) may still result in some impedance mismatch due to practical limits on their physical design, including their actual non-constant impedance that can vary with frequency, and the quality of their connections, particularly after long-term exposure to the elements. This is where the imaginary part of complex impedance, also known as reactance, comes in. Now, that reflected power has to go somewhere, and will either be reflected back to the airwaves on reception, or back into the transmitter on transmission. But just measuring heat generated at the connector may not account for all losses, because the actual dissipation may occur elsewhere. You may not have noticed much or any signal loss due to operating well within usable link budgets, nor noticed much extra heat generation in the body of the HT, but insertion loss from connectors can contribute a small, measurable amount of reduction in signal strength. Probably not something to worry about for an HT talking to a repeater. Perhaps something to worry about for Earth-Moon-Earth at UHF, or mountain-topping at microwave frequencies, or other weak-signal work much above HF. Some links I found on the subject: 1. Pretty Lousy? (PL) 259 Connectors "The underlying assumption with the above statement is connector loss has everything to do with resistive 'heating' losses, has nothing to do with reflective losses, and all loss will reveal itself as heat energy." http://www.hamradio.me/connectors/pr...-the-test.html 2. The UHF type connector under network analysis "Manufactures of UHF plugs and receptors all state that this type connector are of non-constant impedance and are suitable for use up to 200 or 300 MHz, depending on production quality. They also state that the UHF connector can be used up to 500 MHz with a cautionary note of reduced performance." http://www.qsl.net/vk3jeg/pl259tst.html 3. Insertion Loss vs. Transmission Loss "Insertion Loss and Transmission Loss are often confused by hams." http://vk1od.net/transmissionline/concept/iltl.htm 4. N-type vs. SO-239 NO FIGHTING PLEASE! :-) "There's no question that Type N connectors will outperform UHF connectors at VHF and UHF. But unless you're prepared to open up the radio and replace the SO-239 with a Type N, don't sweat the single connection. Just use a UHF-Type N adapter on the back of the rig and go with Type N connectors everywhere else." http://www.eham.net/ehamforum/smf/in...c=68629.0;wap2 5. Insertion loss for RF connector adaptors "1/4 to 1/2 db per connector is the loss I've always heard." http://www.amsat.org/amsat/archive/a.../msg00214.html - -- 73, Paul W. Schleck, K3FU http://www.novia.net/~pschleck/ Finger for PGP Public Key -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (SunOS) iD8DBQFPcK1K6Pj0az779o4RAoL7AJ9VQovYNqZnQP4W22CC2a 2061sFnwCgmdMN VIgz18pm+vorQe1TZN466tQ= =LMnT -----END PGP SIGNATURE----- |
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