{"id":1343,"date":"2016-12-26T16:36:59","date_gmt":"2016-12-26T20:36:59","guid":{"rendered":"http:\/\/www.n4rfc.com\/?p=1343"},"modified":"2016-12-26T16:38:45","modified_gmt":"2016-12-26T20:38:45","slug":"tram-1480-dual-band-antenna","status":"publish","type":"post","link":"https:\/\/www.n4rfc.com\/?p=1343","title":{"rendered":"TRAM 1480 Dual Band Antenna"},"content":{"rendered":"

I was looking for an inexpensive dual band VHF\/UHF antenna to use with my go box radios.\u00a0 I came across a dual band antenna from TRAM on Amazon that was half the price of similar Diamond and Comet dual band antennas.<\/p>\n

The specs for the Tram were advertised as follows:<\/p>\n

Gain: \u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 6 dB on 2m or 8 dB on 70 cm<\/p>\n

VSWR:\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Less than 1.5:1<\/p>\n

Frequency Range:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 144-148 Mhz and 430-450 Mhz<\/p>\n

Polarization:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Vertical<\/p>\n

Impedance:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 50 Ohm<\/p>\n

Configuration:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 5\/8 Wave 2 Element (2m) and 5\/8 Wave 4 Element (70cm)<\/p>\n

Power Capacity:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 200 Watts<\/p>\n

Connector:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 UHF Female<\/p>\n

So I ordered one and in a few days I had it in hand.\u00a0 It was 48 bucks and it was free shipping.\u00a0 Not a bad price at all.<\/p>\n

The antenna was packaged nicely and arrived in good condition.\u00a0 The antenna was shipped in two pieces that were less than 54 inches long.\u00a0 Assembled the antenna is just over 8 ft. at 98 inches long.\u00a0 (Click on the thumbnails to enlarge the photo)<\/p>\n

\"tramdualband-1\"<\/a><\/p>\n

The antenna is very similar in design to the Comet antennas and uses the same mounting system as the Comet antenna with a aluminum sleeve at the bottom of the mount with extruded aluminum brackets and stainless steel U-bolts.\u00a0 It was all neatly packaged and all the parts were there.<\/p>\n

\"tramdualband-2\"<\/a>The antenna requires assembling the two sections using a Allen setscrew.\u00a0 The required Allen wrenches are supplied with the antenna and the assembly is very easy.\u00a0 With a pair of needle nose pliers you pull the center radiator out of the top section and connect it to the pin on the bottom section.<\/p>\n

The two sections are shown here, the bottom on the right and the top on the left.<\/p>\n

\"tramdualband-3\"<\/a><\/p>\n

Shown here with the two sections joined with the setscrew.<\/p>\n

\"tramdualband-4\"<\/a><\/p>\n

Then slide the innards back into the antenna and tighten the coupling nut that seals the two halves of the antenna.<\/p>\n

\"tramdualband-5\"<\/a><\/p>\n

Then add the radials, the mounting sleeve, and clamps and attach it to your mast.<\/p>\n

\"tramdualband-6\"<\/a><\/p>\n

The TRAM Dual Band Antenna assembled and ready for SWR testing.<\/p>\n

I mounted the antenna on a tripod and attached a 50 ohm coax cable and the MFJ Antenna Analyser.\u00a0 Below is the VSWR I measured at several frequencies across the bands:<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n
Frequency<\/td>\nSWR<\/td>\nNote<\/td>\n<\/tr>\n
144.0<\/td>\n2.3:1<\/td>\n<\/td>\n<\/tr>\n
144.5<\/td>\n2.1:1<\/td>\n<\/td>\n<\/tr>\n
145.0<\/td>\n1.8:1<\/td>\n<\/td>\n<\/tr>\n
145.5<\/td>\n1.6:1<\/td>\n<\/td>\n<\/tr>\n
146.0<\/td>\n1.4:1<\/td>\n<\/td>\n<\/tr>\n
146.5<\/td>\n1.3:1<\/td>\n<\/td>\n<\/tr>\n
147.0<\/td>\n1.3:1<\/td>\n<\/td>\n<\/tr>\n
147.5<\/td>\n1.2:1<\/td>\nLow SWR @ 147.4 mhz<\/td>\n<\/tr>\n
148.0<\/td>\n1.3<\/td>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Frequency<\/td>\nSWR<\/td>\nNote<\/td>\n<\/tr>\n
440<\/td>\n1.4:1<\/td>\n<\/td>\n<\/tr>\n
441<\/td>\n1.3:1<\/td>\nLow SWR @ 441.4 mhz<\/td>\n<\/tr>\n
442<\/td>\n1.4:1<\/td>\n<\/td>\n<\/tr>\n
443<\/td>\n1.5:1<\/td>\n<\/td>\n<\/tr>\n
444<\/td>\n1.5:1<\/td>\n<\/td>\n<\/tr>\n
445<\/td>\n1.6:1<\/td>\n<\/td>\n<\/tr>\n
446<\/td>\n1.7:1<\/td>\n<\/td>\n<\/tr>\n
447<\/td>\n1.7:1<\/td>\n<\/td>\n<\/tr>\n
448<\/td>\n1.7:1<\/td>\n<\/td>\n<\/tr>\n
449<\/td>\n1.7:1<\/td>\n<\/td>\n<\/tr>\n
450<\/td>\n1.6:1<\/td>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Well, so much for the VSWR Spec!\u00a0 The SWR reads a bit high on the MFJ.\u00a0 The FM portion of the 2 meter band seems to be pretty useable and the lower section of the UHF where one transmits seems to be usable.\u00a0 In a functional test with a FT-8900 there was no problems.\u00a0 I could hit the repeaters just find and I could get into the 2 Meter packet nodes with no problem.\u00a0 The rig didn\u2019t show any issues with the antenna and it performed nicely.<\/p>\n

All in all, not a bad antenna for 48 bucks.<\/p>\n","protected":false},"excerpt":{"rendered":"

I was looking for an inexpensive dual band VHF\/UHF antenna to use with my go box radios.\u00a0 I came across a dual band antenna from TRAM on Amazon that was half the price of similar Diamond and Comet dual band antennas. The specs for the Tram were advertised as follows: Gain: \u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 6 dB […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7,1],"tags":[],"class_list":["post-1343","post","type-post","status-publish","format-standard","hentry","category-amateur-radio","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/www.n4rfc.com\/index.php?rest_route=\/wp\/v2\/posts\/1343","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.n4rfc.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.n4rfc.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.n4rfc.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.n4rfc.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1343"}],"version-history":[{"count":3,"href":"https:\/\/www.n4rfc.com\/index.php?rest_route=\/wp\/v2\/posts\/1343\/revisions"}],"predecessor-version":[{"id":1358,"href":"https:\/\/www.n4rfc.com\/index.php?rest_route=\/wp\/v2\/posts\/1343\/revisions\/1358"}],"wp:attachment":[{"href":"https:\/\/www.n4rfc.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1343"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.n4rfc.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1343"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.n4rfc.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1343"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}