Can anybody help me into locating someone who can sell me some 2N5179 transistors in OZ. There seems to be a shortage of good parts supplies around these days.
Thanks
Brian VK4QB
Finding Transistors
Re: Finding Transistors
Brian,
Minkits (www.minikits.com.au) list the MPSH10 as a suitable replacement for the 2N5179
Regards
Rod Preston VK4KZR
Minkits (www.minikits.com.au) list the MPSH10 as a suitable replacement for the 2N5179
Regards
Rod Preston VK4KZR
-
VK4QB
Re: Finding Transistors
Thanks Rod,
The MPSH10 is a poor cousin for the 2N5179 whose Ft is shown as 1.4 ghz while the MPSH10 is shown as 600 mhz almost 1/2 of the 2N transistor. I've got a couple but I would like a few more for some uhf builds.
73
Brian 4QB
The MPSH10 is a poor cousin for the 2N5179 whose Ft is shown as 1.4 ghz while the MPSH10 is shown as 600 mhz almost 1/2 of the 2N transistor. I've got a couple but I would like a few more for some uhf builds.
73
Brian 4QB
Re: Finding Transistors
Hi Brian,
In the past, I have used successfully the 2N5770 in circuits/applications which called for a 2N5179. Such applications included oscillator/multiplier circuits to 300+ MHz, multiplier circuits to 500+ MHz and high-speed Schmitt triggers (switching).
The datasheets of various current manufacturers quote the fT (transition frequency) as either 900 MHz or 800 MHz minimum (one quotes 800 MHz typical), but no maximum is quoted.
The 2N5770 has similar small signal gain (Gpe of 15 dB typical at 200 MHz) to the 2N5179, similar collector-base time constant and collector-base capacitance specs.
I don't know any extant suppliers. That'll be your next hurdle
73, Roger Harrison VK2ZRH
In the past, I have used successfully the 2N5770 in circuits/applications which called for a 2N5179. Such applications included oscillator/multiplier circuits to 300+ MHz, multiplier circuits to 500+ MHz and high-speed Schmitt triggers (switching).
The datasheets of various current manufacturers quote the fT (transition frequency) as either 900 MHz or 800 MHz minimum (one quotes 800 MHz typical), but no maximum is quoted.
The 2N5770 has similar small signal gain (Gpe of 15 dB typical at 200 MHz) to the 2N5179, similar collector-base time constant and collector-base capacitance specs.
I don't know any extant suppliers. That'll be your next hurdle
73, Roger Harrison VK2ZRH
-
VK4QB
Re: Finding Transistors
Hi Roger,
Thanks for that info. Ft would appear to be a hit or miss thing with some manufacturers. The problem Ive got is low gain with a linear amp section of a 70 cm transvertor which is running 2N5770s Iv'e got a couple of of 2N5179s which I'll use, but I would like some more. However, I may have to try a BFR 96 instead which would probably be better anyway, and they are available locally.
Thanks
Brian 4QB
Thanks for that info. Ft would appear to be a hit or miss thing with some manufacturers. The problem Ive got is low gain with a linear amp section of a 70 cm transvertor which is running 2N5770s Iv'e got a couple of of 2N5179s which I'll use, but I would like some more. However, I may have to try a BFR 96 instead which would probably be better anyway, and they are available locally.
Thanks
Brian 4QB
Re: Finding Transistors
Brian,VK4QB wrote:Can anybody help me into locating someone who can sell me some 2N5179 transistors in OZ. There seems to be a shortage of good parts supplies around these days.
Thanks
Brian VK4QB
I did not reply initially because I cannot answer your specific question.
My response is essentially "bzzzzt! Wrong question!".
I will say that I have learned that buying parts from some Aussie hobby suppliers is a problem, and without detailing the experience, I firstly try foreign sources for small parts... they are often cheaper, faster and have parts you cannot source here... or only from Farnell etc. It is not that I don't use Aussie suppliers, they just get less than 10% of my spend.
I know some people will not use Ebay or Paypal, but right now there are several sellers offering 2N5179 on Ebay, and if you can get reasonable postage rates from one of them, you should be able to buy a lifetime supply of the things for small money.
Owen
-
VK4QB
Re: Finding Transistors
Thanks Owen,
Thats what I have been suspecting.that the sales are not there as nobody is buying parts. I seem to be one of the few that gets enjoyment with building gear. Have a look at most operators, they list bought stuff. Not that I'm against that, if you can afford it, but we are loosing our electronic ability as a whole by doing that, and the bought stuff has all the bugs ironed out of it anyway. Yes I think you are right, by getting parts from overseas. I did notice that the ARRL and RSGB are concerned about the buying of built stuff and have brought out a CD on designs which you can build yourself. These designs are proven replicable and good for the electronics industry as a whole. Now we have to educate people to go back to build, not buy. Sadly I don't think this is likely to happen.
73
Brian 4QB
Thats what I have been suspecting.that the sales are not there as nobody is buying parts. I seem to be one of the few that gets enjoyment with building gear. Have a look at most operators, they list bought stuff. Not that I'm against that, if you can afford it, but we are loosing our electronic ability as a whole by doing that, and the bought stuff has all the bugs ironed out of it anyway. Yes I think you are right, by getting parts from overseas. I did notice that the ARRL and RSGB are concerned about the buying of built stuff and have brought out a CD on designs which you can build yourself. These designs are proven replicable and good for the electronics industry as a whole. Now we have to educate people to go back to build, not buy. Sadly I don't think this is likely to happen.
73
Brian 4QB
-
VK5ACY
Re: Finding Transistors
Hello Brian VK4QB,
I am one of "the few" operators who try to build their own gear. Recent projects include a 160m solid state AM transmitter, with which I have had contacts. The transistors are mostly 2SC945s which came from eBay for just a few dollars per hundred. With the 2SC945s and a bag of 2N5486 FETs I can have much fun building things for time wasting and self education - which is what AR is meant to include. I keep a selection of new and used transistors scrounged over many years for applications requiring certain qualities and can get most projects to go with a few empirically derived component value changes (select on test !
). This empiric selection is where the self training occurs and anyone can do this if they give it a try. You can look at a circuit for ideas and then build it with available bits and pieces from your junk box.
I am using a home-brew amplifier on 70cm made from salvaged parts using a pair of MRF338s at 28VDC for a fairly clean 150W output, and the metalwork for a bigger amplifier using 4 X MRF338s is almost finished. I had help from Chas, VK3BRZ who cut and prepared the 75 Ohm quarter-wave coax sections for the Wilkinson dividers/combiners, as working small PTFE coax is one of the most difficult tasks to perform with only one hand. I have done this preparation but each termination can take an hour.
My 200W amplifier for 2m was homebuilt about 25 years ago from salvaged DSE 2m kit amplifiers and better bits including all ATC capacitors (also salvaged). The original bias circuit in the kit was not 'stiff' enough and now uses low-impedance transistor bias sources.
All my antennas are home made DL6WU-style built from both salvaged and new aluminium and seem to work well having all states and ZL on 2m and a couple of stations worked via EME, even my tower is salvaged and extended with more salvaged steel.
I reckon everyone should build something, even if it is a simple antenna or bit of test gear....anyone can be an 'appliance operator'.
Bill VK5ACY near Adelaide.
I am one of "the few" operators who try to build their own gear. Recent projects include a 160m solid state AM transmitter, with which I have had contacts. The transistors are mostly 2SC945s which came from eBay for just a few dollars per hundred. With the 2SC945s and a bag of 2N5486 FETs I can have much fun building things for time wasting and self education - which is what AR is meant to include. I keep a selection of new and used transistors scrounged over many years for applications requiring certain qualities and can get most projects to go with a few empirically derived component value changes (select on test !
). This empiric selection is where the self training occurs and anyone can do this if they give it a try. You can look at a circuit for ideas and then build it with available bits and pieces from your junk box.I am using a home-brew amplifier on 70cm made from salvaged parts using a pair of MRF338s at 28VDC for a fairly clean 150W output, and the metalwork for a bigger amplifier using 4 X MRF338s is almost finished. I had help from Chas, VK3BRZ who cut and prepared the 75 Ohm quarter-wave coax sections for the Wilkinson dividers/combiners, as working small PTFE coax is one of the most difficult tasks to perform with only one hand. I have done this preparation but each termination can take an hour.
My 200W amplifier for 2m was homebuilt about 25 years ago from salvaged DSE 2m kit amplifiers and better bits including all ATC capacitors (also salvaged). The original bias circuit in the kit was not 'stiff' enough and now uses low-impedance transistor bias sources.
All my antennas are home made DL6WU-style built from both salvaged and new aluminium and seem to work well having all states and ZL on 2m and a couple of stations worked via EME, even my tower is salvaged and extended with more salvaged steel.
I reckon everyone should build something, even if it is a simple antenna or bit of test gear....anyone can be an 'appliance operator'.
Bill VK5ACY near Adelaide.
Last edited by VK5ACY on Fri Jul 25, 2008 6:37 pm, edited 1 time in total.
-
VK6FKJN
Re: Finding Transistors
You could use e-bay?
The following store is quite good "Activeparts", 2N5946 are $4:10 AUS each.
http://stores.ebay.com.au/Activeparts_W ... 18Q2el1247
Best Regards,
Kyle...
VK6FKJN
The following store is quite good "Activeparts", 2N5946 are $4:10 AUS each.
http://stores.ebay.com.au/Activeparts_W ... 18Q2el1247
Best Regards,
Kyle...
VK6FKJN
-
VK4QB
Re: Finding Transistors
Hi Bill
Thanks for the info on your endevours. I have been building things in the electronics line since I can remember. Getting surplus parts is a bit hard in this location but we scrounge what we can but sometimes it pays to buy good parts. I like your idea of a stiffer bias system for the 2 meter amp as I always felt it was a bit sloppy.
73
Brian 4QB
Thanks for the info on your endevours. I have been building things in the electronics line since I can remember. Getting surplus parts is a bit hard in this location but we scrounge what we can but sometimes it pays to buy good parts. I like your idea of a stiffer bias system for the 2 meter amp as I always felt it was a bit sloppy.
73
Brian 4QB