Where to find HELP for some
particular components
(relays, pin diodes, transistor, capacitors)
Down load this page (parts_suppliers_notes.zip) as a .zip file (.pdf format) <----click here | ||||||||||||||||||||||||||||||||||||||
(as an example and of course from all
others component distributors not here indicated because not known by us). Relays You can try many small relays from different manufacturers that fit in our board space. We have used nowadays available industry standard types (single SPDT dimensions are: long 15.5 mm (.61), large 12 mm. (0.472), high 13.9 mm. (.547) like Nais/Aromat/Omron or other firms and most of them are single SPDT unit otherwise indicated in the schematics. Particular ones: In unit 1 – Low-Pass/High Pass unit the input relay is a Nais/Aromat TX2-12V (a smaller dimension with good isolation per price) pdf file at http://naisrelay.com/ choose PDF catalog, mechanical relays. The same type has been used also in unit 4 - Pin-diodes variable attenuator, also in unit 8 – the RX
out relay only is a SPDT by Nais
TX2-12V (<---click
here for link to .pdf Nais data sheet, same as above It is available from Allied Electronics at http://www.alliedelec.com:
In unit 9 –the PTT activated power supply 13.5Vdc ampls relay switch is an abundant solid one and fast by OMRON G5LE, a 12Vdc SPDT (1 pole 10A) (data sheet in http://www.omron.com, under relay PCB power general types) for longer life. It also available in ALLIED Catalog :
Co-axial RF Power relays (for higher than 150 watts to 250 watts antenna A/B tx/rx selection option) one suitable of many available could be: Tohtsu® The SPST RF reed relay (max up to 100-150 watts CW) by WABASH, 1017-18-1, is in Surplus Sale of Nebraska catalog at http://www.surplussales.com/. It was used to switch the output low pass filters in Rockwell-Collins KWM380, and it is much lower priced than the original Wabash SPDT version). For pre-amplifiers: 2N5109 RF wideband transistor is available in RF PARTS Co (California) catalog at
http://www.rfparts.com/2n.html. Motorola does not produce it anymore but other manufacturers do so you can
find 2N5109 also in MOUSER
catalog (http://www.mouser.com),
see now also
Advanced Power Technology APT Capacitors trimmers: Capacitor trimmers used in the passband filters, if not available the Philips Teflon/film type, you can also use ceramic cap. trimmers as those in Jameco catalog ( http://www.jameco.com, select components, capacitors, ceramic trimmers caps) Pin diodes for variable attenuator
Pin –diodes AGILENT 5082-3081 (<------click here for DATA SHEET)
and also in Newark catalog at http://www.newark.com/ See AGILENT (ex-HP) application note 1048 "A low-Cost Surface Mount Pin diode pi Attenuator" with schematics for a 3 diodes 5082-3081 and a discussion about an even more symmetrical configuration with 4 diodes with test report over the frequency range of 300 KHz to 3GHz. At 10 Mhz it is reported a two-tone third order intermodulation distortion input intercept point around +30dBm for attenuation setting from 10 to 20 dB, and even much better for lower attenuation levels. Updated: 09 aug 2003 |