开云体育

Decibel DB4060 Series Duplexers

Jeff Acree All Messages By This Member #214485 What would be required to change a DB4060 series can that is currently set up for pass low / block high to pass high / block low?? If loop replacement is required, where can they be procured? ? Thanks! Jeff KC8VFN
Harold Farrenkopf All Messages By This Member #214492 I haven’t seen the loop but the can uses a T connector and capacitor so if it’s like the Sinclair style Q loop, it’s the same and just needs to be tuned - there is a notch on both sides of the pass frequency.?
Jeff DePolo WN3A All Messages By This Member #214496 开云体育 The DB4060/4062 series had five different loop assemblies.? Depending on the bandsplit (there are three) and whether the loop is used for high-pass/low-reject versus low-pass/high-reject determines which of the five loop assemblies is needed.? Or to say it another way, for any given bandsplit, two of the five loop assemblies are needed, one type for the high-pass leg and one type for the low-pass leg. ? If the OP will email me what model or frequency range the duplexer is as it stands, I can tell them what to do to convert it to ham band.? I can also provide loops to replace the ones that need to be changed; the trimmer caps are the same regardless so you just need to replace the loop itself.? I can provide cable lengths and other details as well. ? ??????????????????????????????????????????????????????????????????????????????????????????????? --- Jeff WN3A ?
Jeff Acree All Messages By This Member #214519 Jeff, ? I cannot find any labels anywhere on my Duplexers, so I removed the low pass loop housing and took a picture of the bottom of it. ?See attached.? Based on something I read on duplexerrepair.com I was hoping to find information there and I did, but it is hard to read.? ?I noted the longest leg of the loop is about 3.25" from the solder to first bend.? Does any of this help with identification? ? Thanks! Jeff KC8VFN Picture 3.jpg
Jeff DePolo WN3A All Messages By This Member #214524 开云体育 I noted the longest leg of the loop is about 3.25" from the solder to first bend.? Does any of this help with identification? _._,_._,_ Well, maybe can read what’s written better than I can by looking the pic.? The loops should have a part number of 048467, with a suffix of -001 through -005.? If you can make out those designators on the loops you have, send me an inventory of what you have via direct email and we can go from there.? ? If the straight leg of the loop (i.e. the side connected to the center pin of the connector) is 3-1/2” as you reported, that’s a -005 which is a keeper – that loop is used on the high-pass side of a ham-band “B” split duplexer.? ? BUT, based on what I can see in the pic, it looks like it is marked -004, which would be 3-1/4” on the long leg.? So, either your measurement is off a bit (i.e. 3-1/2” vs 3-1/4”), or my eyesight is failing me and it’s not a -004. ? ??????????????????????????????????????????????????????????????????????????????????????????????? --- Jeff WN3A ?
mistuff All Messages By This Member #214544 Going thru my old notes, the 3.25 dimension corresponds to a loop part number -004.? ? ?The 3.50 dimension is a -005 loop. ? -004 loops are standard for typical public safety band duplexers (nominally 155Mhz). ? According to the article in repeaterbuilders, for the ham band, the high pass cans (notch low) should have a -005 loop and the low pass cans (notch high) should have a -004 loop. NOTE, the loops affect where the tuning CAP is adjusted to create the notch. From my experience, they don't significantly affect the band pass adjustment. ? I've easily tuned cans from the public safety bands (all loops -004) without any problems. I guess it's possible changing one set of cans from -004 to -005 (make 1/4 in longer) could change the notch shape slightly BUT, those caps are VERY sensitive to soldering and I don't think the risk is worth changing the loop length without first trying using the public safety cans (with -004 loops). ? ? ? ? ?

Previous Topic Next Topic