[AMRadio] FS: VT-4C, Coax Adapters
For Sale 6 used VT-4C (211) tubes. These all test strong (very strong, like new) on my emission tester. All are G.E. brand. No boxes. Probably stolen from helpless BC-375 and -191 transmitters. $50 each. All 6 for $250. 16 PL-259 to SO-239 coax right angles. $2 each or $25 for all. All are used, mostly silver-plated, ex-military UG-6464/U. Mostly Amphenol. 2 coax T adapters M-358. These have 2 SO-239 back-to back with a PL-259 sticking out in the middle. $2 each 5 PL-259 to PL-259 male to male barrel conectors. 2 are brand new. 3 are beat up and used. $7/all So-239 to SO-239 barrel adapters. New, silver-plated Amphenol, still in packaging. $2.50 each. 5 available. SO-239 to SO-239 barrel adapters. Used, silver-plated Amphenol. Mostly look new. $2 each. 5 available. Tee Adapters. These are new silver-plated Amphenol in the packaging. The T is back-to-back SO-239s with a PL-259 in the middle. $3 each. 4 available. Bulkhead SO-239 socket. These are the kind that mount with 4 screws around the edges of the socket. New, silver-plated Amphenol, in the packaging. $1.50 each. 3 to sell. PL-259 cable size reducer insert. This is the insert that screws into a PL-259 so it can be used with RG-58. There are 17 of these, new Amphenol, in the packaging. $6/all More PL-259 inserts. 11 of them in 2 packages. Not Amphenol. Plated with nickel or some alloy. Brand new. $4/all. OFF TOPIC, don't look... Samsung SIR-T150 HDTV receiver (set-top-box). This is a 3 year old receiver that I purchased new in 2002 for $373 (ouch!). I have always used it for off-the-air HDTV reception. I have never used it with cable but it would work fine in that role. Being older, this does not have some of the fancy features of the latest receivers. For instance, there is no Dolby Digital sound, etc. Also, I have never used any of the features it has like output for a computer monitor so I know nothing about how those work. All I ever did with this was plug in an antenna, connect component video and stereo audio out to my TV and turn it on. Working as-designed with original manual and remote control. I may have the box here somewhere too. The networks are finally getting serious about originating much of their prime-time content in high-def. I guarantee that once you see a football game in HD, you will never go back. This is probably not a good receiver for the afficionado. But it would be a good way for someone to get their feet wet in HD. $50 Thanks for looking. 73, Don Merz, N3RHT The information contained in this e-mail may be confidential and is intended solely for the use of the named addressee. Access, copying or re-use of the e-mail or any information contained therein by any other person is not authorized. If you are not the intended recipient please notify us immediately by returning the e-mail to the originator.(A)
[AMRadio] Triplett 310-FET Meter
I was given this meter and it seems like it ought to have potential. Problem is the batteries. I got a manual for it from Triplett (free snail-mailed photocopy!--amazing in 2005). It needs 2 batteries. The 1.5 volt job is still made as the ASA N cell. But the small 7 volt battery is a problem. It is no longer made and I don't see anything that is both physically and electrically close... Does anyone else have this meter? If so, what do you do for batteries? The 310-FET is a handheld, analog VOM/VTVM with a 10 meg input impedance. It seems very well built. The voltage ranges are limited to 600V (whereas a VTVM would typically go upwards of 1500) but that should be fine for casual use. Anyway, I'd like to sue this meter. But I'd like it to have all of it's required batteries. The Triplett web site old gear FAQ makes an honest, wry comment about their choices of batteries of their equipment over the years... 73, Don Merz, N3RHT The information contained in this e-mail may be confidential and is intended solely for the use of the named addressee. Access, copying or re-use of the e-mail or any information contained therein by any other person is not authorized. If you are not the intended recipient please notify us immediately by returning the e-mail to the originator.(A)
Re: [AMRadio] Triplett 310-FET Meter
Hello Don, I know you are upset about the battery problem, but suing the meter? That really seems a bit harsh. 73, Bruce WA8TNC = Merz Donald S wrote: I was given this meter and it seems like it ought to have potential. Problem is the batteries. It needs 2 batteries. The 1.5 volt job is still made as the ASA N cell. But the small 7 volt battery is a problem. It is no longer made and I don't see anything that is both physically and electrically close... Anyway, I'd like to sue this meter 73, Don Merz, N3RHT -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.300 / Virus Database: 265.6.9 - Release Date: 1/6/2005
RE: [AMRadio] Triplett 310-FET Meter Batteries Found
A quick thanks to the list members for the excellent response. The batteries were found on the Radio Shack web site. Thanks folks. 73, Don Merz, N3RHT -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Merz Donald S Sent: Monday, January 10, 2005 11:13 AM To: 'Amradio (E-mail); 'Glowbugs (E-mail) Subject: [AMRadio] Triplett 310-FET Meter I was given this meter and it seems like it ought to have potential. Problem is the batteries. I got a manual for it from Triplett (free snail-mailed photocopy!--amazing in 2005). It needs 2 batteries. The 1.5 volt job is still made as the ASA N cell. But the small 7 volt battery is a problem. It is no longer made and I don't see anything that is both physically and electrically close... Does anyone else have this meter? If so, what do you do for batteries? The 310-FET is a handheld, analog VOM/VTVM with a 10 meg input impedance. It seems very well built. The voltage ranges are limited to 600V (whereas a VTVM would typically go upwards of 1500) but that should be fine for casual use. Anyway, I'd like to sue this meter. But I'd like it to have all of it's required batteries. The Triplett web site old gear FAQ makes an honest, wry comment about their choices of batteries of their equipment over the years... 73, Don Merz, N3RHT The information contained in this e-mail may be confidential and is intended solely for the use of the named addressee. Access, copying or re-use of the e-mail or any information contained therein by any other person is not authorized. If you are not the intended recipient please notify us immediately by returning the e-mail to the originator.(A) __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net The information contained in this e-mail may be confidential and is intended solely for the use of the named addressee. Access, copying or re-use of the e-mail or any information contained therein by any other person is not authorized. If you are not the intended recipient please notify us immediately by returning the e-mail to the originator.(A)
[AMRadio] AM Amps
I just bought a Johnson Ranger and wonder if my 30L1 or Henry 2KD would work okay. 811's in the 30L1 and a pair of 3-500's in the Henry. Thanks. Dick/K5DIC _ On the road to retirement? Check out MSN Life Events for advice on how to get there! http://lifeevents.msn.com/category.aspx?cid=Retirement
Re: [AMRadio] AM Amps
Sure they will Dick!! Just drive them easy at first, key down AM operation seems to bring out the gremlins in amplifiers!! W5SUM -- Original Message --- From: RICHARD W GILLESPIE [EMAIL PROTECTED] To: amradio@mailman.qth.net Sent: Mon, 10 Jan 2005 17:58:38 -0700 Subject: [AMRadio] AM Amps I just bought a Johnson Ranger and wonder if my 30L1 or Henry 2KD would work okay. 811's in the 30L1 and a pair of 3-500's in the Henry. Thanks. Dick/K5DIC _ On the road to retirement? Check out MSN Life Events for advice on how to get there! http://lifeevents.msn.com/category.aspx?cid=Retirement __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net --- End of Original Message ---
Re: [AMRadio] AM Amps
Hi Dick The 30L1 would far too over stressed but the Henry would be perfect, by the way thanks for buying my Ranger, 73 Chris RICHARD W GILLESPIE wrote: I just bought a Johnson Ranger and wonder if my 30L1 or Henry 2KD would work okay. 811's in the 30L1 and a pair of 3-500's in the Henry. Thanks. Dick/K5DIC _ On the road to retirement? Check out MSN Life Events for advice on how to get there! http://lifeevents.msn.com/category.aspx?cid=Retirement __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net
Re: [AMRadio] AM Amps
I partially disagree, but with a -big- proviso. You'll have to find a way to reduce the Ranger output to the 10-15 watt level. Maybe the nicest way to do that is a variable screen voltage control, similar to what you'll find here: http://www.w3am.com/ranger.html but I'm sure there are other methods. Just don't run the stock Ranger straight into the amp without dealing with this in some way. Don't ask the 30L1 to do more than ~125 watts carrier. The 811's can't handle much dissipation. Same is true for the SB200 and its pair of 572B's. But they both will work fine like this. I ran an SB200 like this for a long time. Bigger amps with more plate dissipation, like the Henry or SB-220 are a safer bet, but you must be very careful nonetheless. 73, g Chris wrote: Hi Dick The 30L1 would far too over stressed but the Henry would be perfect, by the way thanks for buying my Ranger, 73 Chris RICHARD W GILLESPIE wrote: I just bought a Johnson Ranger and wonder if my 30L1 or Henry 2KD would work okay. 811's in the 30L1 and a pair of 3-500's in the Henry. Thanks. Dick/K5DIC
Re: [AMRadio] AM Amps
Here is a ruff rule of thumb for amps on AM: If the amp takes 100 watts to drive it on ssb then it will take 100 watts pep of AM to drive it. 100 watts pep of AM means 25 watts of carrier with 100% modulation. You will also get 25% of the carrier out of the amp from it's pep output level. If it puts out 600 watts pep (collins 30L1) then you will get 150 watts carrier out when properly set up. If it took 100 watts pep to drive it on ssb it will take 25 watts carrier on AM. To see if the tubes will handle it figure the dissipation backwards. At 150 watts output that amp should be at around 33% efficiency (if properly tuned). 150 watts divided by 33% = 454 watts plate input power. Now subtract the 150 watts of output power you are getting from the 454 watts input power and you have around 304 watts going to heat in the plates. In the case of the 30L1 divide that by 4 (the number of tubes) and that leave about 76 watts per tube in dissipation. 811A's have a 65 watt plate dissipation ratting. So you are a little over. For short transmissions you can get by with it but no long buzzard transmissions. The power supply in the 30L1 is marginal also. It will get mighty hot. The other Gary's suggestion of limiting to 125 watts carrier out (500 watts pep)gets you right in the ball park on plate dissipation. 125 divided by 33% = 378 watts input. Subtract the 125 watts and that leaves 253 watts dissipated. Divide by 4 and that is about 63 watts per tube. For proper loading on the amplifier operating at 125 watts out with carrier it should be tuned for 500 watts output pep. The drive required can be figured pretty close by first calculating the gain of the amp at 600 watts output, its rated output. If it takes 100 watts to drive it to that output power that is a gain of 6. At 500 watts out the amp will still have a gain of 6 so divide 500 by 6 which gives about 83 watts pep of drive. divide that by 4 for the carrier needed. That should be around 20 watts. Keep in mind that the amp needs to be tuned at the pep level. One way to do that is to modulate the 20 watt carrier 100% with a tone or a long hlooo and tune the amp watching a scope. Another way is to use the ssb rig with an 80 watt carrier driving the amp and tune it for max output. Then hook the AM rig up with the 20 watts drive. You can roughly check to see if you tuned the amp right by looking at the efficiency that it is running when you think you have it tuned. Calculate the input power, plate current times plate volts. Divide the output power you are seeing on the watt meter by the input power. If the efficiency is around 30 to 35% you should be in the ballpark. Any greater efficiency and it tells you that amp is not loaded heavy enough. Or you have too much drive. More than you wanted to know. 73 Gary K4FMX Gary Blau wrote: I partially disagree, but with a -big- proviso. You'll have to find a way to reduce the Ranger output to the 10-15 watt level. Maybe the nicest way to do that is a variable screen voltage control, similar to what you'll find here: http://www.w3am.com/ranger.html but I'm sure there are other methods. Just don't run the stock Ranger straight into the amp without dealing with this in some way. Don't ask the 30L1 to do more than ~125 watts carrier. The 811's can't handle much dissipation. Same is true for the SB200 and its pair of 572B's. But they both will work fine like this. I ran an SB200 like this for a long time. Bigger amps with more plate dissipation, like the Henry or SB-220 are a safer bet, but you must be very careful nonetheless. 73, g Chris wrote: Hi Dick The 30L1 would far too over stressed but the Henry would be perfect, by the way thanks for buying my Ranger, 73 Chris RICHARD W GILLESPIE wrote: I just bought a Johnson Ranger and wonder if my 30L1 or Henry 2KD would work okay. 811's in the 30L1 and a pair of 3-500's in the Henry. Thanks. Dick/K5DIC
Re: [AMRadio] AM Amps
Gary Blau wrote: I partially disagree, but with a -big- proviso. You'll have to find a way to reduce the Ranger output to the 10-15 watt level. Maybe the nicest way to do that is a variable screen voltage control, similar to what you'll find here: http://www.w3am.com/ranger.html but I'm sure there are other methods. Reducing the B+ level on the plate of the 6146 is another way. Just don't run the stock Ranger straight into the amp without dealing with this in some way. A T connector, and a dummy load works well, also. Just tossing out some more ideas. 73 W5OMR
