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Beware ICOM 746 owners! Do not use on 60 meters.
I'm passing this info along because I thought it was important for the group
(and before someone damages the radio they worked so hard for). The below email was a response from an ICOM tech after an amateur op inquired about the performance of the 746 and 746 Pro on 60 meters. Take the info for what its worth. 73 de Paul Good Morning.... Thanks for your e-mail. The 746 final PA band pass filters were never designed to support operation outside of the amateur radio bands. They will "stretch" to accept normal operation in the MARS and CAP frequencies just above and just below the amateur radio spectrum, but they will not support operation down in the 5 MHz area. They will heat up and you will damage the radio. About the only two radios will have reasonable operation on the 5 MHz area are the 706MkIIG and the 718. Best Regards; Mike Hilton Technical Support Representative ICOM America, Inc. 2380 116th Ave. NE Bellevue, WA 98004 Ph. (425) 454-7619 Fax (425) 637-8417 www.icomamerica.com |
Hmmm, mine works OK! I have made numerous QSOs on 60m
but most were during the first week that it was opened! Nothing melted in mine. On Sat, 22 Nov 2003 08:37:02 -0500, "Paul Vanasse" wrote: I'm passing this info along because I thought it was important for the group (and before someone damages the radio they worked so hard for). The below email was a response from an ICOM tech after an amateur op inquired about the performance of the 746 and 746 Pro on 60 meters. Take the info for what its worth. 73 de Paul Good Morning.... Thanks for your e-mail. The 746 final PA band pass filters were never designed to support operation outside of the amateur radio bands. They will "stretch" to accept normal operation in the MARS and CAP frequencies just above and just below the amateur radio spectrum, but they will not support operation down in the 5 MHz area. They will heat up and you will damage the radio. About the only two radios will have reasonable operation on the 5 MHz area are the 706MkIIG and the 718. Best Regards; Mike Hilton Technical Support Representative ICOM America, Inc. 2380 116th Ave. NE Bellevue, WA 98004 Ph. (425) 454-7619 Fax (425) 637-8417 www.icomamerica.com |
Hmmm, mine works OK! I have made numerous QSOs on 60m
but most were during the first week that it was opened! Nothing melted in mine. On Sat, 22 Nov 2003 08:37:02 -0500, "Paul Vanasse" wrote: I'm passing this info along because I thought it was important for the group (and before someone damages the radio they worked so hard for). The below email was a response from an ICOM tech after an amateur op inquired about the performance of the 746 and 746 Pro on 60 meters. Take the info for what its worth. 73 de Paul Good Morning.... Thanks for your e-mail. The 746 final PA band pass filters were never designed to support operation outside of the amateur radio bands. They will "stretch" to accept normal operation in the MARS and CAP frequencies just above and just below the amateur radio spectrum, but they will not support operation down in the 5 MHz area. They will heat up and you will damage the radio. About the only two radios will have reasonable operation on the 5 MHz area are the 706MkIIG and the 718. Best Regards; Mike Hilton Technical Support Representative ICOM America, Inc. 2380 116th Ave. NE Bellevue, WA 98004 Ph. (425) 454-7619 Fax (425) 637-8417 www.icomamerica.com |
Hmmm, mine works OK! I have made numerous QSOs on 60m but most were during the first week that it was opened! Nothing melted in mine. YET! I think the prudent thing to do is make sure you are running relatively low power when operating on 60M. You are supposed to be running maximum of 50W ERP. I'd think 10 or 20 watts out of the transmitter would prevent over-heating of the band pass filter components. Ed WB6SAT |
Hmmm, mine works OK! I have made numerous QSOs on 60m but most were during the first week that it was opened! Nothing melted in mine. YET! I think the prudent thing to do is make sure you are running relatively low power when operating on 60M. You are supposed to be running maximum of 50W ERP. I'd think 10 or 20 watts out of the transmitter would prevent over-heating of the band pass filter components. Ed WB6SAT |
On Tue, 25 Nov 2003 23:12:36 GMT, "Ed G."
wrote: Hmmm, mine works OK! I have made numerous QSOs on 60m but most were during the first week that it was opened! Nothing melted in mine. YET! I think the prudent thing to do is make sure you are running relatively low power when operating on 60M. You are supposed to be running maximum of 50W ERP. I'd think 10 or 20 watts out of the transmitter would prevent over-heating of the band pass filter components. Ed WB6SAT Yeah - that makes sense. Thank you. If I go on 60 m again I will do just that. |
On Tue, 25 Nov 2003 23:12:36 GMT, "Ed G."
wrote: Hmmm, mine works OK! I have made numerous QSOs on 60m but most were during the first week that it was opened! Nothing melted in mine. YET! I think the prudent thing to do is make sure you are running relatively low power when operating on 60M. You are supposed to be running maximum of 50W ERP. I'd think 10 or 20 watts out of the transmitter would prevent over-heating of the band pass filter components. Ed WB6SAT Yeah - that makes sense. Thank you. If I go on 60 m again I will do just that. |
The problem is to get the 10-20w out of the radio you may have to shove 100w
into the filter, and that's what hurts. You need to monitor the current drawn to determine if there is a possibility of damage. -- Clif Holland, KA5IPF AVVid Authorized Kenwood and Icom Service Center 816 W Shady Grove Rd Irving, TX 75060 www.avvid.com 1-800-214-5779 972-870-0630 (Local) "Ed G." wrote in message .. . Hmmm, mine works OK! I have made numerous QSOs on 60m but most were during the first week that it was opened! Nothing melted in mine. YET! I think the prudent thing to do is make sure you are running relatively low power when operating on 60M. You are supposed to be running maximum of 50W ERP. I'd think 10 or 20 watts out of the transmitter would prevent over-heating of the band pass filter components. Ed WB6SAT |
The problem is to get the 10-20w out of the radio you may have to shove 100w
into the filter, and that's what hurts. You need to monitor the current drawn to determine if there is a possibility of damage. -- Clif Holland, KA5IPF AVVid Authorized Kenwood and Icom Service Center 816 W Shady Grove Rd Irving, TX 75060 www.avvid.com 1-800-214-5779 972-870-0630 (Local) "Ed G." wrote in message .. . Hmmm, mine works OK! I have made numerous QSOs on 60m but most were during the first week that it was opened! Nothing melted in mine. YET! I think the prudent thing to do is make sure you are running relatively low power when operating on 60M. You are supposed to be running maximum of 50W ERP. I'd think 10 or 20 watts out of the transmitter would prevent over-heating of the band pass filter components. Ed WB6SAT |
"Clif Holland" wrote in message ... The problem is to get the 10-20w out of the radio you may have to shove 100w into the filter, and that's what hurts. You need to monitor the current drawn to determine if there is a possibility of damage. Give this man a cigar because he's today's exclusive winner on 21! The problem is that most modern hams today don't have a clue about what you're talking about because most modern hams don't understand the theory behind bandpass filtration, especially in their own Riceboxes. They actually believe the radios will go from DC to Daylight once opened. I believe this is the reason why Yaesu, Kenwood, and Icom haven't publicly released the mods to these radios (other than to MARS/CAP members) because these companies know damn well that they'll be performing a slue of warranty repairs on the lot because some jack ass will actually try to use his radio on the commercial AM broadcast band. |
"Clif Holland" wrote in message ... The problem is to get the 10-20w out of the radio you may have to shove 100w into the filter, and that's what hurts. You need to monitor the current drawn to determine if there is a possibility of damage. Give this man a cigar because he's today's exclusive winner on 21! The problem is that most modern hams today don't have a clue about what you're talking about because most modern hams don't understand the theory behind bandpass filtration, especially in their own Riceboxes. They actually believe the radios will go from DC to Daylight once opened. I believe this is the reason why Yaesu, Kenwood, and Icom haven't publicly released the mods to these radios (other than to MARS/CAP members) because these companies know damn well that they'll be performing a slue of warranty repairs on the lot because some jack ass will actually try to use his radio on the commercial AM broadcast band. |
On Thu, 27 Nov 2003 07:14:37 -0500, "Paul Vanasse"
wrote: I believe this is the reason why Yaesu, Kenwood, and Icom haven't publicly released the mods to these radios (other than to MARS/CAP members) because these companies know damn well that they'll be performing a slue of warranty repairs on the lot because some jack ass will actually try to use his radio on the commercial AM broadcast band. So far, Ten Tec is the only one, I know of, offering specifics on getting on 60 meters. For their rigs, it's a simple software download. Bob k5qwg |
On Thu, 27 Nov 2003 07:14:37 -0500, "Paul Vanasse"
wrote: I believe this is the reason why Yaesu, Kenwood, and Icom haven't publicly released the mods to these radios (other than to MARS/CAP members) because these companies know damn well that they'll be performing a slue of warranty repairs on the lot because some jack ass will actually try to use his radio on the commercial AM broadcast band. So far, Ten Tec is the only one, I know of, offering specifics on getting on 60 meters. For their rigs, it's a simple software download. Bob k5qwg |
"Paul Vanasse" wrote in
news:VUlxb.6898$LV1.6847@okepread05: "Clif Holland" wrote in message ... The problem is to get the 10-20w out of the radio you may have to shove 100w into the filter, and that's what hurts. You need to monitor the current drawn to determine if there is a possibility of damage. Though I can't speak for the 746Pro I can firmly state that the BP filter for the 746 DOES cover the 60 meter segment. It is spec'd for 4.0 to 8.0 MHz. Measurements in the lab showed no difference between the current draw vs output power between 40 and 60 Meters. Assuming your antenna presents a good match, you should be confident that the 746 will perform just fine and within specs when modified for 60 meter operation. 73 Dave Give this man a cigar because he's today's exclusive winner on 21! The problem is that most modern hams today don't have a clue about what you're talking about because most modern hams don't understand the theory behind bandpass filtration, especially in their own Riceboxes. They actually believe the radios will go from DC to Daylight once opened. I believe this is the reason why Yaesu, Kenwood, and Icom haven't publicly released the mods to these radios (other than to MARS/CAP members) because these companies know damn well that they'll be performing a slue of warranty repairs on the lot because some jack ass will actually try to use his radio on the commercial AM broadcast band. |
"Paul Vanasse" wrote in
news:VUlxb.6898$LV1.6847@okepread05: "Clif Holland" wrote in message ... The problem is to get the 10-20w out of the radio you may have to shove 100w into the filter, and that's what hurts. You need to monitor the current drawn to determine if there is a possibility of damage. Though I can't speak for the 746Pro I can firmly state that the BP filter for the 746 DOES cover the 60 meter segment. It is spec'd for 4.0 to 8.0 MHz. Measurements in the lab showed no difference between the current draw vs output power between 40 and 60 Meters. Assuming your antenna presents a good match, you should be confident that the 746 will perform just fine and within specs when modified for 60 meter operation. 73 Dave Give this man a cigar because he's today's exclusive winner on 21! The problem is that most modern hams today don't have a clue about what you're talking about because most modern hams don't understand the theory behind bandpass filtration, especially in their own Riceboxes. They actually believe the radios will go from DC to Daylight once opened. I believe this is the reason why Yaesu, Kenwood, and Icom haven't publicly released the mods to these radios (other than to MARS/CAP members) because these companies know damn well that they'll be performing a slue of warranty repairs on the lot because some jack ass will actually try to use his radio on the commercial AM broadcast band. |
The problem is to get the 10-20w out of the radio you may have to shove 100w into the filter, and that's what hurts. You need to monitor the current drawn to determine if there is a possibility of damage. If you are having the above problem, then there's something wrong with you radio. My 746Pro puts out nearly full power on 60M, as it does on all other bands with absolutely NO change in current draw. If the default 40M filter was attenuating the 60M signal that much it would sure show up on the watt meter! Ed WB6SAT |
The problem is to get the 10-20w out of the radio you may have to shove 100w into the filter, and that's what hurts. You need to monitor the current drawn to determine if there is a possibility of damage. If you are having the above problem, then there's something wrong with you radio. My 746Pro puts out nearly full power on 60M, as it does on all other bands with absolutely NO change in current draw. If the default 40M filter was attenuating the 60M signal that much it would sure show up on the watt meter! Ed WB6SAT |
Anyone that understands the operation of solid state PA sections with band
pass filtering for each band would not risk using the rig out of band. It may not of hurt anything yet but why risk it. In time it will catch up to you. The filters are designed to present a safe matched impedeance to the PA for a specific frequency range and attentuate any spurs. Icom says no...what about "dont do it " dont you understand? Gary |
Anyone that understands the operation of solid state PA sections with band
pass filtering for each band would not risk using the rig out of band. It may not of hurt anything yet but why risk it. In time it will catch up to you. The filters are designed to present a safe matched impedeance to the PA for a specific frequency range and attentuate any spurs. Icom says no...what about "dont do it " dont you understand? Gary |
On Sun, 07 Dec 2003 17:06:15 GMT, "Gary Poland" wrote:
Anyone that understands the operation of solid state PA sections with band pass filtering for each band would not risk using the rig out of band. It may not of hurt anything yet but why risk it. In time it will catch up to you. The filters are designed to present a safe matched impedeance to the PA for a specific frequency range and attentuate any spurs. Icom says no...what about "dont do it " dont you understand? Gary Probably the same part that hundreds of others of us "don't understand", who are enjoying our IC746 rigs every day on 60m ya numbskull! |
On Sun, 07 Dec 2003 17:06:15 GMT, "Gary Poland" wrote:
Anyone that understands the operation of solid state PA sections with band pass filtering for each band would not risk using the rig out of band. It may not of hurt anything yet but why risk it. In time it will catch up to you. The filters are designed to present a safe matched impedeance to the PA for a specific frequency range and attentuate any spurs. Icom says no...what about "dont do it " dont you understand? Gary Probably the same part that hundreds of others of us "don't understand", who are enjoying our IC746 rigs every day on 60m ya numbskull! |
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