[Repeater-Builder] Silver plating of cavities advice please?
Hi All, I have rescently obtained a uhf pair of cavities that are not silver plated inside (bare copper) They both have an insertion loss of 3dBIf I were to get them silver plated what would the improvement be? I have no idea how much it would cost but if the saving was only about 0.5dB I wouldn't bother. Your thoughts please? Cheers Dave UZN
[Repeater-Builder] Re: Silver plating of cavities advice please?
Dave dave_g7...@... wrote: Hi All, I have rescently obtained a uhf pair of cavities that are not silver plated inside (bare copper) They both have an insertion loss of 3dB In this example the 3dB insertion loss is not is not affected (to any significant value) by the lack of silver plating. If I were to get them silver plated what would the improvement be? The person/business you pay to complete the plating has an improved income. I have no idea how much it would cost but if the saving was only about 0.5dB I wouldn't bother. Don't bother... Your thoughts please? I try not to have any... Cheers Dave UZN Never watched the show and I believe it was on the UPN out here. :-) On a more serious note... you might look around for pictures and descriptions of the very famous Motorola T-1500 series of cavities often made into various combination of duplexer assemblies. They are not plated and they work very well. The insertion loss is set by the probe type and position. s.
Re: [Repeater-Builder] Re: Silver plating of cavities advice please?
Skipp, Did you ever work with Rowan and Martin?!! Very good as usual. Doug On 11/07/2010 14:21:32, skipp025 (skipp...@yahoo.com) wrote: Dave dave_g7...@... wrote: Hi All, I have rescently obtained a uhf pair of cavities that are not silver plated inside (bare copper) They both have an insertion loss of 3dB In this example the 3dB insertion loss is not is not affected (to any significant value) by the lack of silver plating. If I were to get them silver plated what would the improvement be? The person/business you pay to complete the plating has an improved income. I have no idea how much it would cost but if the saving was only about 0.5dB I wouldn't bother. Don't bother... Your thoughts please? I try not to have any... Cheers Dave UZN Never watched the show and I believe it was on the UPN out here. :-) On a more serious note... you might look around for pictures and descriptions of the very famous Motorola T-1500 series of cavities often made into various combination of duplexer assemblies. They are not plated and they work very well. The insertion loss is set by the probe type and position. s. %0
[Repeater-Builder] Re: Silver plating of cavities advice please?
Thanks for that SkippI accept your opinions but in that case why do some manufactures silver plate the insides and some don't? Cheers Dave UZN --- In Repeater-Builder@yahoogroups.com, skipp025 skipp...@... wrote: Dave dave_g7uzn@ wrote: Hi All, I have rescently obtained a uhf pair of cavities that are not silver plated inside (bare copper) They both have an insertion loss of 3dB In this example the 3dB insertion loss is not is not affected (to any significant value) by the lack of silver plating. If I were to get them silver plated what would the improvement be? The person/business you pay to complete the plating has an improved income. I have no idea how much it would cost but if the saving was only about 0.5dB I wouldn't bother. Don't bother... Your thoughts please? I try not to have any... Cheers Dave UZN Never watched the show and I believe it was on the UPN out here. :-) On a more serious note... you might look around for pictures and descriptions of the very famous Motorola T-1500 series of cavities often made into various combination of duplexer assemblies. They are not plated and they work very well. The insertion loss is set by the probe type and position. s.
[Repeater-Builder] Re: Silver plating of cavities advice please?
I can't speak for the manufactures, but I think silver plating them would cut down on the chance of the cavities oxidizing over time. So that is why I would have them plated.
Re: [Repeater-Builder] Re: Silver plating of cavities advice please?
Silver plating can have an impressive positive performance effect under some circumstances. It's also at advantage because it's corrosion result is conductive, so performance is not effected by tarnishing. -- mailto:o...@ozindfw.net Oz POB 93167 Southlake, TX 76092 (Near DFW Airport)
Re: [Repeater-Builder] Re: Silver plating of cavities advice please?
On 7/11/2010 11:46 AM, Oz-in-DFW wrote: Silver plating can have an impressive positive performance effect under some circumstances. It's also at advantage because it's corrosion result is conductive, so performance is not effected by tarnishing. -- mailto:o...@ozindfw.net mailto:oz%40ozindfw.net Oz POB 93167 Southlake, TX 76092 (Near DFW Airport) _ Hit the *(^$% send button too fast. If the manufacturer didn't bother to plate them, I wouldn't either. -- mailto:o...@ozindfw.net Oz POB 93167 Southlake, TX 76092 (Near DFW Airport)
[Repeater-Builder] UHF Isolater needed
Good morning, Like the header says, UHF isolator needed for 440.500 any suggestions? Thanks Brian, k5in
[Repeater-Builder] Re: Silver plating of cavities advice please?
Dave dave_g7...@... wrote: Thanks for that SkippI accept your opinions but in that case why do some manufactures silver plate the insides and some don't? Cheers Dave UZN Hi Dave, Please don't accept my opinions as gospel, always try to obtain information from multiple sources following up on the stated facts for accuracy. There are two major reasons considered by many people for silver plating coil and cavity surfaces. Q and Oxidation Let's talk about both in reverse order... [pasted text from another reply post] I can't speak for the manufactures, but I think silver plating them would cut down on the chance of the cavities oxidizing over time. Silver does oxidize, just less/slower than bare copper. The environment becomes the relative pivot point in your choice to plate or nay. I have 1970's vintage bare copper cavities in clean, cool, dry locations that still look shinny/new. Many of the internally not silver plated Motorola T-1500 Duplexers are real-world examples still in active service. Q is everything if you really need it... but in this example you only need enough Q to get the job done. And in the cavities we're talking about here you should be able to obtain enough Q for the job. One of the rare examples I've really seen the obvious benefits of Silver Plating is in the field of NMR Probe Design Construction. A way off topic application for this group... but proof to me there is real merit to silver plating if you need it. In many examples for UHF/VHF Amateur Duplexer applications I'd say silver plating is not an in-stone requirement. Just beneficial if you do... cheers, s. Dave dave_g7uzn@ wrote: Hi All, I have rescently obtained a uhf pair of cavities that are not silver plated inside (bare copper) They both have an insertion loss of 3dB In this example the 3dB insertion loss is not is not affected (to any significant value) by the lack of silver plating. If I were to get them silver plated what would the improvement be? The person/business you pay to complete the plating has an improved income. I have no idea how much it would cost but if the saving was only about 0.5dB I wouldn't bother. Don't bother... Your thoughts please? I try not to have any... Cheers Dave UZN Never watched the show and I believe it was on the UPN out here. :-) On a more serious note... you might look around for pictures and descriptions of the very famous Motorola T-1500 series of cavities often made into various combination of duplexer assemblies. They are not plated and they work very well. The insertion loss is set by the probe type and position. s.
[Repeater-Builder] Re: Silver plating of cavities advice please?
Skipp, Did you ever work with Rowan and Martin?!! Doug Hi Doug, One must always keep a real sense of humor to keep from otherwise screaming at the lunatics I/we have to deal with on a daily basis. The key is to avoid giving the real lunatics your home or cell phone number. :-) s. PS: I do enjoy listening to Ernestine the Telephone Operator skits on the XM Satellite Radio Comedy Channels. Though just a coincidence... I think.
[Repeater-Builder] UHF Repeater Amps For Sale
I have two UHF repeater Amps for sale 1. TPL PA6-1BE 8 - 20 watts in 70 - 100 watts out, continuous duty. $ 275 includes shipping. 2. GE MASTR II PL19D424895G32 1/2 watt in 110 watts out $ 250, not sure, but I think this is cont. duty, has a real big heatsink. includes shipping. Both work in ham band. Bob W2XL 845-417-1894 or e-mail
Re: [Repeater-Builder] UHF Repeater Amps For Sale
Could you shoot me a photo of the TPL PA6-1BE ? _ Eddie Cope wb5hhz --- On Sun, 7/11/10, wb2bxl w...@hvc.rr.com wrote: From: wb2bxl w...@hvc.rr.com Subject: [Repeater-Builder] UHF Repeater Amps For Sale To: Repeater-Builder@yahoogroups.com Date: Sunday, July 11, 2010, 2:34 PM I have two UHF repeater Amps for sale 1. TPL PA6-1BE 8 - 20 watts in 70 - 100 watts out, continuous duty. $ 275 includes shipping. 2. GE MASTR II PL19D424895G32 1/2 watt in 110 watts out $ 250, not sure, but I think this is cont. duty, has a real big heatsink. includes shipping. Both work in ham band. Bob W2XL 845-417-1894 or e-mail
Re: [Repeater-Builder] UHF Repeater Amps For Sale
I'd also be interested in a photo. Thanks. Hal Brueseke KA9MXW - Original Message - From: Eddie Cope To: Repeater-Builder@yahoogroups.com Sent: Sunday, July 11, 2010 5:42 PM Subject: Re: [Repeater-Builder] UHF Repeater Amps For Sale Could you shoot me a photo of the TPL PA6-1BE ? _ Eddie Cope wb5hhz --- On Sun, 7/11/10, wb2bxl w...@hvc.rr.com wrote: From: wb2bxl w...@hvc.rr.com Subject: [Repeater-Builder] UHF Repeater Amps For Sale To: Repeater-Builder@yahoogroups.com Date: Sunday, July 11, 2010, 2:34 PM I have two UHF repeater Amps for sale 1. TPL PA6-1BE 8 - 20 watts in 70 - 100 watts out, continuous duty. $ 275 includes shipping. 2. GE MASTR II PL19D424895G32 1/2 watt in 110 watts out $ 250, not sure, but I think this is cont. duty, has a real big heatsink. includes shipping. Both work in ham band. Bob W2XL 845-417-1894 or e-mail
Re: [Repeater-Builder] Phoenix S model
I have 1 GE Phoenix psx200 that I would part with. I would like to trade for 1 Motorola RADIUS (NOT MAXTRAC) UHF 2 ch 25 watt radio. Jeff n5sxq n5sx...@charter.net dwmcg...@bellsouth.net dwmcg...@bellsouth.net wrote: Anybody have any VHF or UHF Phoesnix S models they are willing to get rid of---sell or swap. Wanting the narrowband version and the 2 channel will be okay. Reply to dwmcg...@bellsouth.net Thanks, Dale K0JXI
[Repeater-Builder] Re-tuning MSR-2000 Channel Elements.
Hi everyone, I am going to post this message here because batlabs didn't approve my post. Apparently it's too harsh to tell people, PLEASE DO NOT TELL ME TO HAVE SOMEONE ELSE DO IT. I am looking for information on how exactly to re-tune a channel element for a MSR repeater. I've seen instructions as far as what to adjust on the element itself, but what I really need to know is; what equipment is required, how to hook that equipment up to the channel element, and what to look for while adjusting the channel element. Now I realize that I need a new crystal as well, and I realize it can all be done professionally with temperature compensation. But what I want to know is how I can do it myself just to get started and make sure everything is going to work the way I want before I pay out big bucks to have it all done the right way. I have an extra set of channel elements, so playing around with one set isn't going to affect having the other set done professionally if I mess something up. Thanks for any help you can give me, Jeff - KB1SPH / WQEX694
[Repeater-Builder] Recrystal MSR-2000 Channel Elements (and a guacamole recipe)
Recrystal MSR-2000 Channel Elements Path_Finder.Geo kb1...@... wrote: Hi everyone, I am going to post this message here because batlabs didn't approve my post. Apparently it's too harsh to tell people, PLEASE DO NOT TELL ME TO HAVE SOMEONE ELSE DO IT. Hi Jeff, Apparently you do not play the BatLabs Game very well? I'm sure you'll survive with the ever so perky bunch over here. I am looking for information on how exactly to re-tune a channel element for a MSR repeater. I've seen instructions as far as what to adjust on the element itself, but what I really need to know is; what equipment is required, how to hook that equipment up to the channel element, and what to look for while adjusting the channel element. The transmit channel element is best adjusted for frequency center by using a Communications Service Monitor setup to sample (off the on-air signal) read the main carrier channel/frequency. The simple way to set the IDC Control/Pot is to set the Transmit CTCSS (PL) Tone deviation to about 750Hz. In a stock MSR-2000 the repeat audio level is then set using the level pot on the Squelch Gate Module. If you don't have access to a Service Monitor, a decent Frequency Counter will at least let you net (adjust) the frequency to F-center (on the desired frequency). If you move the transmitter more than say... 500 kHz from its last alignment location, you should repeat the Service Manual Alignment steps on or near the new frequency. The Receiver is a different animal. Take the Receiver frequency and add and/or subtract the receiver IF frequency (most often 10.7 or 10.8 MHz for the VHF Receiver). The formula you use depends on your receivers IF Frequency and Injection Chain, which translates to which side of the IF the multiplied crystal frequency ends up on. In your example it's probably F-frequency minus the IF Frequency equals the multiplied Channel Element injection frequency, which is what you want to set/align. Put a X1 Scope/Text Probe on your Service Monitor (or Frequency Counter) Antenna (Low Level RF) Input and place it down onto/near the receiver circuit board. You can also use a decent quality frequency counter if you're more careful. At some location on or near the board you will be able to monitor and measure the output of the RX Channel Element Frequency, then set it for the expected Injection Frequency. As an example: A receive frequency of 151.625 MHz minus a 10.7 IF frequency equals 140.925 MHz. Sniff around the receiver board until you observe a signal in that area, then net (adjust) the channel element frequency to the expected 140.925 F-center location. If you can't find the expected frequency you might run the numbers for a 10.8 IF Frequency and sniff around 140.825 for the channel element injection frequency. In both the above examples, a X1 (times-1) Scope Probe or something similar is handy to use. If you can't get/find a signal, make a short antenna probe by clipping a small length of insulated regular wire onto the end of the probe. The end of the wire held by the Scope Probe jaws should obviously be stripped bare. Try not to allow the sampling wire and/or probe to directly contact/short any of the exposed metal parts on the receiver board. Now I realize that I need a new crystal as well, and I realize it can all be done professionally with temperature compensation. Yeah but in many cases professional is a lot more expensive than it really has to be. But what I want to know is how I can do it myself just to get started and make sure everything is going to work the way I want before I pay out big bucks to have it all done the right way. I have an extra set of channel elements, so playing around with one set isn't going to affect having the other set done professionally if I mess something up. For me there are two regular places to order crystals. The first is International Crystal Manufacturing, always high quality but you will find the pricing a bit steep for any casual crystal/channel element work. The second location for me is Bomar, where I pretty much buy all my channel element crystals. Their quality, pricing and wait time is in my opinion more than fair. Their only down side (to me) is their $50 min order amount. So you might need to order a few extra crystals to make an order amount. Not a problem if you think ahead or pal-up with someone else to place an order. I call Bomar with a Visa Card in the other hand, tell them I want Crystals for Mitrek/MSR-2000 Channel Elements KXN-1086 and KXN-1088 types. There are other MSR Channel Element numbers you can use, but the above model numbers are the most popular and should be interchangeable with anything you might have. At a price of about $15/$20 per crystal (last time I had some cut) I order at least 4 crystals to make the min order amount. Wait the normal time (they do have rush service for more $$)
RE: [Repeater-Builder] Re: Silver plating of cavities advice please?
Silver plate does help in the long run if you travel miles twice a year to clean + polish then plating wil reduce/stop tarnish and might help Q , as for insertion lose improvements sometimes _ Browse profiles for FREE! Meet local singles online. http://clk.atdmt.com/NMN/go/150855801/direct/01/
