Topband: Any experience with 2N3553?
Don, Thank you for confirming the eBay part is not the same as the one sourced from Digikey/Mouser. I have a couple from eBay (at a $1 a piece I could not resist LOL), and a bunch from Digikey. The eBay ones will be discarded immediately, before I get distracted and forget about it. I'm curious about the following: 1) Kits advertised online, but not on eBay. I don't have the link handy, but I remember the pictures clearly showing the same 'Motorola' part I purchased on ebay; 2) When one buys assembled boards on eBay. Do they use original parts or counterfeit ones? 73 de Vince, VA3VF _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Any experience with 2N3553?
I would certainly be interested in how the Asia 5109's checkMy experience with Asian semiconductors has not been 100%...Hal/WB4AEG On Thu, 19 Mar 2020 14:42:24 -0400 Richard (Rick) Karlquist wrote On 3/19/2020 10:04 AM, Don Kirk wrote: > For grins and giggles I ordered 10 2N5109 parts on E-bay (from Asia). Also > ordered new ones from Mouser which I just received today, and also had one > that I purchased a long time ago from Mouser (all of my Mouser purchased > Just FYI, > Don (wd8dsb) > _ I used the 2N3553 45 years ago as a medium power RF amplifier, but not as a 2N5109 substitute. I don't know that it has the high and flat current gain and the low base spreading resistance of the 2N5109 family. That didn't matter for my application. Remember that Motorola stopped making 2N5109's in the year 2000. Therefore any transistor with a Motorola logo and a date code newer than 2000 is a prima fascia counterfeit. I just received 20 each of the Central Semiconductor 2N5109's from Mouser. If I were going to evaluate transistors claiming to be 2N5109, I would want to check: 1. DC current gain (beta), both the peak value and the uniformity of beta vs collector current. 2. f-sub-T 3. Base spreading resistance. This is determined indirectly by measuring noise figure. Depending on the application, one of more of these could be important. Rick N6RK _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Any experience with 2N3553?
On 3/19/2020 10:04 AM, Don Kirk wrote: For grins and giggles I ordered 10 2N5109 parts on E-bay (from Asia). Also ordered new ones from Mouser which I just received today, and also had one that I purchased a long time ago from Mouser (all of my Mouser purchased Just FYI, Don (wd8dsb) _ I used the 2N3553 45 years ago as a medium power RF amplifier, but not as a 2N5109 substitute. I don't know that it has the high and flat current gain and the low base spreading resistance of the 2N5109 family. That didn't matter for my application. Remember that Motorola stopped making 2N5109's in the year 2000. Therefore any transistor with a Motorola logo and a date code newer than 2000 is a prima fascia counterfeit. I just received 20 each of the Central Semiconductor 2N5109's from Mouser. If I were going to evaluate transistors claiming to be 2N5109, I would want to check: 1. DC current gain (beta), both the peak value and the uniformity of beta vs collector current. 2. f-sub-T 3. Base spreading resistance. This is determined indirectly by measuring noise figure. Depending on the application, one of more of these could be important. Rick N6RK _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Any experience with 2N3553?
For grins and giggles I ordered 10 2N5109 parts on E-bay (from Asia). Also ordered new ones from Mouser which I just received today, and also had one that I purchased a long time ago from Mouser (all of my Mouser purchased ones are marked CEN on their sides whereas the ones from Asia are identified as being Motorola (Motorola Emblem on their top). I built up a simple common emitter amplifier on a white plug in experimenter board to make simple voltage gain measurements, and the Asia parts as suspected by others do not appear to be authentic. 1) The old and new Mouser purchased 2N5109 transistors measure similar to each other (gain within 0.8 dB at 25 MHz). 2) At 0.5 MHz the Asia transistors have slightly more gain (about +0.8 dB), but at 25 MHz the Asia transistors definitely have less gain (average of -2.8 dB) 3) Plotting the gain versus frequency of the various transistors show the slope of the curves are similar between my old and new Mouser purchased 2N5109's, whereas the Asia purchased 2N5109's have a much more negative gain versus frequency slope indicating they are definitely not similar in performance. I requested a refund for the ones I purchased from Asia under the complaint that they "Do Not Appear Authentic" which is one of the choices to pick from on the E-bay refund request system and also provided my data, and the seller very quickly refunded my purchase. Just FYI, Don (wd8dsb) _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Any experience with 2N3553?
Hi Lee, Gee, you think they are using the same 16 x 20 mil die for both parts? :-) Both parts will be around for a very long time. They just might be expensive. The space folks like them because you can get radiation hardened parts. And following MIL-PRF-19500 specs parts are very close in performance from lot to lot. You can get them in TO-39 cans rated at 1W or UB surface mount packages rated at .5W. Or you can get die and enjoy mounting them. There is no plastic encapsulated transistors for mil and space transistors. By the way in regards to JFETS it depends on which wafer fab they are made in regards to quality and performance from part to part. One company on the west coast that shut down several years ago had two wafer fabs - one in CA and one in AS. The CA fab made the mil wafers and the one in AS made the commercial wafers. The mil wafers were fairly consistent in performance from wafer to wafer. Not so for the commercial wafers. There still is significant stock of wafers after all of these years to build "new" JFETS, both commercial and mil. The switch from TO-cans to surface mount continues to grow. For one, the price of the TO-headers is going up at a fast rate. Some packages are no longer available such as the TO-59. And pick and place is easier with the surface mount components. Oh, and all of these real cheap Fairchild wafers are just about all gone. Folks are scrambling for replacement of the 10 -30 cent die. 73, N2TK, Tony -Original Message- From: Lee STRAHAN [mailto:k7...@msn.com] Sent: Sunday, July 01, 2018 8:40 PM To: N2TK, Tony ; mar...@ok1rr.com; topband@contesting.com Subject: RE: Topband: Any experience with 2N3553? Thanks Tony, Agreed the 2N5109 will be around for a long time however as you point out they are or will be very expensive. At present I use 100's of 2N3866 transistors which are very close to the same die if not selected from the 2N5109 process. My cost in 100 quantity has gone from about $1.60 each to currently $4.00 each in about 2 years' time for 2N3866's. The 5109 is currently priced less at $2.22 where the 3866 used to be less. From all this I conclude that the 2N5109 will follow the huge price increases. I could be wrong but I will not plan on using the 5109 especially where most things are going to surface mount also. Even J-310 FETs have gone from <$.20 to $2.41 at 100 level. Worst thing is 20% of the off brand j-310s don’t meet spec. The only way to solve this is to go to surface mount where you can still get the good J-310 and other great devices. One can often use more than one SMD device in an amplifier having it cost less than one expensive leaded device. For the hams building a single amplifier the 5109 makes a lot of sense right now. Semiconductor times are changing rapidly. I make lots of top-band antenna systems using lots of already expensive electronics. For this reason I have to do as well as I can to predict the future for my products. My observation is that leaded parts are disappearing rapidly and this will continue. LeeK7TJR Hi-Z Antennas -Original Message- From: N2TK, Tony Sent: Sunday, July 1, 2018 2:03 PM To: 'Lee STRAHAN' ; mar...@ok1rr.com; topband@contesting.com Subject: RE: Topband: Any experience with 2N3553? The 2N5109 will be around for many years. It is widely used in the military and space community. It is listed as a JAN part. But it ain't cheap. 73, N2TK, Tony -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Lee STRAHAN Sent: Sunday, July 01, 2018 2:15 PM To: mar...@ok1rr.com; topband@contesting.com Subject: Re: Topband: Any experience with 2N3553? Hello Martin and all, The 2N3553 device was plagued with a low Ft (high at its introduction) making it mostly a low frequency device with questionable high gain high frequency use in typical ham preamps. It is no longer available through the original manufacturers. Also perhaps you are thinking of the BFQ18A and not the BFQ19A device. The BFQ19 is at end of its life cycle and in addition the 18A is widely used now in the MATV industry for wideband amplifiers. I have some experience with the 18A using it in a wideband Norton style amplifier where it is providing 10+dB of gain with a measured noise figure of 2 dB on 160 meters. Its typical IMD is at least listed at UHF on the data sheet. My IMD testing setup is not adequate to test the range of this device but I can say that it exceeds any other amplifiers I have built to date. I typically use the 2N3866 which unfortunately is pricing itself out of the market now. I suspect the 2N5109 will follow as inventories shrink.. A pair of the 18A devices at ~$1.00 USD each single price in a push pull Norton configuration would in my opinion make it worth trying as a killer wideband amp. Just my $.02 USD. Lee K7TJR OR -Original Message- From: Topband On Behalf Of Martin Kratoska Sent:
Re: Topband: Any experience with 2N3553?
On 7/2/2018 3:17 AM, Tim Shoppa wrote: I believe the old Clifton Labs pages had some nice info on JFET parameters. Can't get to anymore? W7ZOI has a nice page on measuring IDSS which I recall to be the parameter on the spec sheet most relevant: http://w7zoi.net/jfet101.pdf Measuring IDSS only takes a 10V power supply and a milliameter, very easy. It is not unusual for JFETs/MOSFETs to have a specified IDSS that covers a range of 10:1. Any experimenter should get proficient at measuring IDSS and understanding how it matters to the application circuit. Also, the IDSS of a particular batch might be in a much narrower range, but the next batch is not guaranteed to repeat. HP used a FET in one of their products where it was easy to calculate that the circuit would not work over the full specified range of IDSS. In spite of this, the product successfully shipped for a few years ... until the latest batch of FETs didn't work, due to a change in IDSS. Rick N6RK _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Any experience with 2N3553?
I believe the old Clifton Labs pages had some nice info on JFET parameters. Can't get to anymore? W7ZOI has a nice page on measuring IDSS which I recall to be the parameter on the spec sheet most relevant: http://w7zoi.net/jfet101.pdf Measuring IDSS only takes a 10V power supply and a milliameter, very easy. I bought a good stock of TO92 J310's before they were obsoleted. The SMD parts are still super available and easy to attach flying leads to (usually you'll tack the gate down to ground anyway leaving two flying leads.) Tim N3QE On Mon, Jul 2, 2018 at 3:25 AM, Martin Kratoska wrote: > Lee, > > very interesting. Many thanks for that valuable info! BTW is there any > easy, cheap and quick method to test the J310, possibly without need of > dedicated complex 'test jig'? > > 73, > Martin, OK1RR > > > Dne 2.7.2018 v 02:39 Lee STRAHAN napsal(a): > > Thanks Tony, >> Agreed the 2N5109 will be around for a long time however as you point >> out they are or will be very expensive. At present I use 100's of 2N3866 >> transistors which are very close to the same die if not selected from the >> 2N5109 process. My cost in 100 quantity has gone from about $1.60 each to >> currently $4.00 each in about 2 years' time for 2N3866's. The 5109 is >> currently priced less at $2.22 where the 3866 used to be less. From all >> this I conclude that the 2N5109 will follow the huge price increases. I >> could be wrong but I will not plan on using the 5109 especially where most >> things are going to surface mount also. Even J-310 FETs have gone from >> <$.20 to $2.41 at 100 level. Worst thing is 20% of the off brand j-310s >> don’t meet spec. The only way to solve this is to go to surface mount where >> you can still get the good J-310 and other great devices. One can often use >> more than one SMD device in an amplifier having it cost less than one >> expensive leaded device. For the hams building a single amplifier the 5109 >> makes a lot of sense right now. Semiconductor times are changing rapidly. I >> make lots of top-band antenna systems using lots of already expensive >> electronics. For this reason I have to do as well as I can to predict the >> future for my products. My observation is that leaded parts are >> disappearing rapidly and this will continue. >> >> LeeK7TJR >> Hi-Z Antennas >> >> -Original Message- >> From: N2TK, Tony >> Sent: Sunday, July 1, 2018 2:03 PM >> >> To: 'Lee STRAHAN' ; mar...@ok1rr.com; >> topband@contesting.com >> Subject: RE: Topband: Any experience with 2N3553? >> >> The 2N5109 will be around for many years. It is widely used in the >> military and space community. It is listed as a JAN part. But it ain't >> cheap. >> 73, >> N2TK, Tony >> >> -Original Message- >> From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Lee >> STRAHAN >> Sent: Sunday, July 01, 2018 2:15 PM >> To: mar...@ok1rr.com; topband@contesting.com >> Subject: Re: Topband: Any experience with 2N3553? >> >> Hello Martin and all, >> The 2N3553 device was plagued with a low Ft (high at its >> introduction) making it mostly a low frequency device with questionable >> high gain high frequency use in typical ham preamps. It is no longer >> available through the original manufacturers. Also perhaps you are thinking >> of the BFQ18A and not the BFQ19A device. The BFQ19 is at end of its life >> cycle and in addition the 18A is widely used now in the MATV industry for >> wideband amplifiers. I have some experience with the 18A using it in a >> wideband Norton style amplifier where it is providing 10+dB of gain with a >> measured noise figure of 2 dB on 160 meters. Its typical IMD is at least >> listed at UHF on the data sheet. My IMD testing setup is not adequate to >> test the range of this device but I can say that it exceeds any other >> amplifiers I have built to date. I typically use the 2N3866 which >> unfortunately is pricing itself out of the market now. I suspect the 2N5109 >> will follow as inventories shrink.. A pair of the 18A devices at ~$1.00 USD >> each single price in a push pull Norton configuration would in my opinion >> make it worth trying as a killer wideband amp. >> Just my $.02 USD. >> Lee K7TJR OR >> >> -Original Message- >> From: Topband On Behalf Of Martin >> Kratoska >> Sent: Sunday, July 1, 2018 9:51 AM >> To: topband@contesting.com >> Subject: Topband: Any experience with 2N3553? >> >> The 2N3553 is a brutal 7 watt device in a TO-39 metal package. Chris >> Trask, N7ZM
Re: Topband: Any experience with 2N3553?
Lee, very interesting. Many thanks for that valuable info! BTW is there any easy, cheap and quick method to test the J310, possibly without need of dedicated complex 'test jig'? 73, Martin, OK1RR Dne 2.7.2018 v 02:39 Lee STRAHAN napsal(a): Thanks Tony, Agreed the 2N5109 will be around for a long time however as you point out they are or will be very expensive. At present I use 100's of 2N3866 transistors which are very close to the same die if not selected from the 2N5109 process. My cost in 100 quantity has gone from about $1.60 each to currently $4.00 each in about 2 years' time for 2N3866's. The 5109 is currently priced less at $2.22 where the 3866 used to be less. From all this I conclude that the 2N5109 will follow the huge price increases. I could be wrong but I will not plan on using the 5109 especially where most things are going to surface mount also. Even J-310 FETs have gone from <$.20 to $2.41 at 100 level. Worst thing is 20% of the off brand j-310s don’t meet spec. The only way to solve this is to go to surface mount where you can still get the good J-310 and other great devices. One can often use more than one SMD device in an amplifier having it cost less than one expensive leaded device. For the hams building a single amplifier the 5109 makes a lot of sense right now. Semiconductor times are changing rapidly. I make lots of top-band antenna systems using lots of already expensive electronics. For this reason I have to do as well as I can to predict the future for my products. My observation is that leaded parts are disappearing rapidly and this will continue. LeeK7TJR Hi-Z Antennas -Original Message- From: N2TK, Tony Sent: Sunday, July 1, 2018 2:03 PM To: 'Lee STRAHAN' ; mar...@ok1rr.com; topband@contesting.com Subject: RE: Topband: Any experience with 2N3553? The 2N5109 will be around for many years. It is widely used in the military and space community. It is listed as a JAN part. But it ain't cheap. 73, N2TK, Tony -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Lee STRAHAN Sent: Sunday, July 01, 2018 2:15 PM To: mar...@ok1rr.com; topband@contesting.com Subject: Re: Topband: Any experience with 2N3553? Hello Martin and all, The 2N3553 device was plagued with a low Ft (high at its introduction) making it mostly a low frequency device with questionable high gain high frequency use in typical ham preamps. It is no longer available through the original manufacturers. Also perhaps you are thinking of the BFQ18A and not the BFQ19A device. The BFQ19 is at end of its life cycle and in addition the 18A is widely used now in the MATV industry for wideband amplifiers. I have some experience with the 18A using it in a wideband Norton style amplifier where it is providing 10+dB of gain with a measured noise figure of 2 dB on 160 meters. Its typical IMD is at least listed at UHF on the data sheet. My IMD testing setup is not adequate to test the range of this device but I can say that it exceeds any other amplifiers I have built to date. I typically use the 2N3866 which unfortunately is pricing itself out of the market now. I suspect the 2N5109 will follow as inventories shrink.. A pair of the 18A devices at ~$1.00 USD each single price in a push pull Norton configuration would in my opinion make it worth trying as a killer wideband amp. Just my $.02 USD. Lee K7TJR OR -Original Message- From: Topband On Behalf Of Martin Kratoska Sent: Sunday, July 1, 2018 9:51 AM To: topband@contesting.com Subject: Topband: Any experience with 2N3553? The 2N3553 is a brutal 7 watt device in a TO-39 metal package. Chris Trask, N7ZMY mentioned some unparalleled IM characterics '... The BFQ19 (made by NXP née Philips) and the NE46134 (made by NEC) are both highly popular within the CATV industry, and are virtually identical in terms of linearity. They compare favorably to the 2N5109 in terms of linearity, though they pale in camparison with the 2N3553 (as do all the others)...'. See http://www.home.earthlink.net/~christrask/Bipolar%20Transistor%20Evaluation.pdf 2N3553 is often mentioned in transmitting applications but I was unable to find some other details like IM, noise and gain characteristics in high DR preamps for receiving purposes. Any experience? 73, Martin, OK1RR _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Any experience with 2N3553?
Thanks Tony, Agreed the 2N5109 will be around for a long time however as you point out they are or will be very expensive. At present I use 100's of 2N3866 transistors which are very close to the same die if not selected from the 2N5109 process. My cost in 100 quantity has gone from about $1.60 each to currently $4.00 each in about 2 years' time for 2N3866's. The 5109 is currently priced less at $2.22 where the 3866 used to be less. From all this I conclude that the 2N5109 will follow the huge price increases. I could be wrong but I will not plan on using the 5109 especially where most things are going to surface mount also. Even J-310 FETs have gone from <$.20 to $2.41 at 100 level. Worst thing is 20% of the off brand j-310s don’t meet spec. The only way to solve this is to go to surface mount where you can still get the good J-310 and other great devices. One can often use more than one SMD device in an amplifier having it cost less than one expensive leaded device. For the hams building a single amplifier the 5109 makes a lot of sense right now. Semiconductor times are changing rapidly. I make lots of top-band antenna systems using lots of already expensive electronics. For this reason I have to do as well as I can to predict the future for my products. My observation is that leaded parts are disappearing rapidly and this will continue. LeeK7TJR Hi-Z Antennas -Original Message- From: N2TK, Tony Sent: Sunday, July 1, 2018 2:03 PM To: 'Lee STRAHAN' ; mar...@ok1rr.com; topband@contesting.com Subject: RE: Topband: Any experience with 2N3553? The 2N5109 will be around for many years. It is widely used in the military and space community. It is listed as a JAN part. But it ain't cheap. 73, N2TK, Tony -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Lee STRAHAN Sent: Sunday, July 01, 2018 2:15 PM To: mar...@ok1rr.com; topband@contesting.com Subject: Re: Topband: Any experience with 2N3553? Hello Martin and all, The 2N3553 device was plagued with a low Ft (high at its introduction) making it mostly a low frequency device with questionable high gain high frequency use in typical ham preamps. It is no longer available through the original manufacturers. Also perhaps you are thinking of the BFQ18A and not the BFQ19A device. The BFQ19 is at end of its life cycle and in addition the 18A is widely used now in the MATV industry for wideband amplifiers. I have some experience with the 18A using it in a wideband Norton style amplifier where it is providing 10+dB of gain with a measured noise figure of 2 dB on 160 meters. Its typical IMD is at least listed at UHF on the data sheet. My IMD testing setup is not adequate to test the range of this device but I can say that it exceeds any other amplifiers I have built to date. I typically use the 2N3866 which unfortunately is pricing itself out of the market now. I suspect the 2N5109 will follow as inventories shrink.. A pair of the 18A devices at ~$1.00 USD each single price in a push pull Norton configuration would in my opinion make it worth trying as a killer wideband amp. Just my $.02 USD. Lee K7TJR OR -Original Message- From: Topband On Behalf Of Martin Kratoska Sent: Sunday, July 1, 2018 9:51 AM To: topband@contesting.com Subject: Topband: Any experience with 2N3553? The 2N3553 is a brutal 7 watt device in a TO-39 metal package. Chris Trask, N7ZMY mentioned some unparalleled IM characterics '... The BFQ19 (made by NXP née Philips) and the NE46134 (made by NEC) are both highly popular within the CATV industry, and are virtually identical in terms of linearity. They compare favorably to the 2N5109 in terms of linearity, though they pale in camparison with the 2N3553 (as do all the others)...'. See http://www.home.earthlink.net/~christrask/Bipolar%20Transistor%20Evaluation.pdf 2N3553 is often mentioned in transmitting applications but I was unable to find some other details like IM, noise and gain characteristics in high DR preamps for receiving purposes. Any experience? 73, Martin, OK1RR _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Any experience with 2N3553?
The 2N5109 will be around for many years. It is widely used in the military and space community. It is listed as a JAN part. But it ain't cheap. 73, N2TK, Tony -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Lee STRAHAN Sent: Sunday, July 01, 2018 2:15 PM To: mar...@ok1rr.com; topband@contesting.com Subject: Re: Topband: Any experience with 2N3553? Hello Martin and all, The 2N3553 device was plagued with a low Ft (high at its introduction) making it mostly a low frequency device with questionable high gain high frequency use in typical ham preamps. It is no longer available through the original manufacturers. Also perhaps you are thinking of the BFQ18A and not the BFQ19A device. The BFQ19 is at end of its life cycle and in addition the 18A is widely used now in the MATV industry for wideband amplifiers. I have some experience with the 18A using it in a wideband Norton style amplifier where it is providing 10+dB of gain with a measured noise figure of 2 dB on 160 meters. Its typical IMD is at least listed at UHF on the data sheet. My IMD testing setup is not adequate to test the range of this device but I can say that it exceeds any other amplifiers I have built to date. I typically use the 2N3866 which unfortunately is pricing itself out of the market now. I suspect the 2N5109 will follow as inventories shrink.. A pair of the 18A devices at ~$1.00 USD each single price in a push pull Norton configuration would in my opinion make it worth trying as a killer wideband amp. Just my $.02 USD. Lee K7TJR OR -Original Message- From: Topband On Behalf Of Martin Kratoska Sent: Sunday, July 1, 2018 9:51 AM To: topband@contesting.com Subject: Topband: Any experience with 2N3553? The 2N3553 is a brutal 7 watt device in a TO-39 metal package. Chris Trask, N7ZMY mentioned some unparalleled IM characterics '... The BFQ19 (made by NXP née Philips) and the NE46134 (made by NEC) are both highly popular within the CATV industry, and are virtually identical in terms of linearity. They compare favorably to the 2N5109 in terms of linearity, though they pale in camparison with the 2N3553 (as do all the others)...'. See http://www.home.earthlink.net/~christrask/Bipolar%20Transistor%20Evaluation.pdf 2N3553 is often mentioned in transmitting applications but I was unable to find some other details like IM, noise and gain characteristics in high DR preamps for receiving purposes. Any experience? 73, Martin, OK1RR _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Any experience with 2N3553?
Hello Martin and all, The 2N3553 device was plagued with a low Ft (high at its introduction) making it mostly a low frequency device with questionable high gain high frequency use in typical ham preamps. It is no longer available through the original manufacturers. Also perhaps you are thinking of the BFQ18A and not the BFQ19A device. The BFQ19 is at end of its life cycle and in addition the 18A is widely used now in the MATV industry for wideband amplifiers. I have some experience with the 18A using it in a wideband Norton style amplifier where it is providing 10+dB of gain with a measured noise figure of 2 dB on 160 meters. Its typical IMD is at least listed at UHF on the data sheet. My IMD testing setup is not adequate to test the range of this device but I can say that it exceeds any other amplifiers I have built to date. I typically use the 2N3866 which unfortunately is pricing itself out of the market now. I suspect the 2N5109 will follow as inventories shrink.. A pair of the 18A devices at ~$1.00 USD each single price in a push pull Norton configuration would in my opinion make it worth trying as a killer wideband amp. Just my $.02 USD. Lee K7TJR OR -Original Message- From: Topband On Behalf Of Martin Kratoska Sent: Sunday, July 1, 2018 9:51 AM To: topband@contesting.com Subject: Topband: Any experience with 2N3553? The 2N3553 is a brutal 7 watt device in a TO-39 metal package. Chris Trask, N7ZMY mentioned some unparalleled IM characterics '... The BFQ19 (made by NXP née Philips) and the NE46134 (made by NEC) are both highly popular within the CATV industry, and are virtually identical in terms of linearity. They compare favorably to the 2N5109 in terms of linearity, though they pale in camparison with the 2N3553 (as do all the others)...'. See http://www.home.earthlink.net/~christrask/Bipolar%20Transistor%20Evaluation.pdf 2N3553 is often mentioned in transmitting applications but I was unable to find some other details like IM, noise and gain characteristics in high DR preamps for receiving purposes. Any experience? 73, Martin, OK1RR _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Any experience with 2N3553?
On 7/1/2018 9:50 AM, Martin Kratoska wrote: The 2N3553 is a brutal 7 watt device in a TO-39 metal package. Chris Trask, N7ZMY mentioned some unparalleled IM characterics I used one of these 40 years ago to build a 95 MHz power oscillator to excite a rubidium plasma lamp in an HP rubidium frequency standard. It was indeed bulletproof, although I was only generating about 2 watts IIRC. I'm sure the data sheet says nothing about IMD or even beta vs collector current because these are of no importance for the intended application. BTW, the 2N3553 was already at least 10 years old even in 1979. If you want to get into the re-purposing game, you have to characterize each individual transistor for the characteristics that count. A curve tracer is easy to come by, and you can also build a socketed amplifier to do IMD testing on. I wonder if N7ZMY has a good design for a homebrew two tone generator, which is the main obstacle for IMD testing. This is especially the case for something as ubiquitous and disparate as the 2N. You never know what you are going to get beyond what the JEDEC number specifies. Experts at NIST due this kind of thing regarding phase noise, and the 2N was one of their favorites. But they tested every one themselves. Rick N6RK _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Any experience with 2N3553?
The 2N3553 is a brutal 7 watt device in a TO-39 metal package. Chris Trask, N7ZMY mentioned some unparalleled IM characterics '... The BFQ19 (made by NXP née Philips) and the NE46134 (made by NEC) are both highly popular within the CATV industry, and are virtually identical in terms of linearity. They compare favourably to the 2N5109 in terms of linearity, though they pale in camparison with the 2N3553 (as do all the others)...'. See http://www.home.earthlink.net/~christrask/Bipolar%20Transistor%20Evaluation.pdf 2N3553 is often mentioned in transmitting applications but I was unable to find some other details like IM, noise and gain characteristics in high DR preamps for receiving purposes. Any experience? 73, Martin, OK1RR _ Topband Reflector Archives - http://www.contesting.com/_topband
