Hi i just got an old pager PA and I`m planning to convert it for 2m use. For
this project I need to put in two relays for bypassing the amp while
receiving. Can anyone recommend the relays?
I`m also thinking of putting in a relay to take the power of the PA module
while receiving to protect the transistors.

Any hints and kinks will help me allot.

Geir

It is an 100w pa.
Any names or numbers will help
"Gregg" wrote in message
news:xa%Dd.5345$06.2801@clgrps12...
For low power (10W), a reed relay. Else, a RF solenoid perhaps would be
in order.

--
Gregg t3h g33k
"Ratings are for transistors....tubes have guidelines"
http://geek.scorpiorising.ca

On Sun, 9 Jan 2005 10:04:43 +0100, "geir knutsen"
wrote:

It is an 100w pa.
Any names or numbers will help
"Gregg" wrote in message
news:xa%Dd.5345$06.2801@clgrps12...
For low power (10W), a reed relay. Else, a RF solenoid perhaps would be
in order.

for HF almost anything will work

---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm

It is one of the Magnetic 8172 on your web.
The plan is to take out the circulator and place the TX relay there instead.
The LP-filter I`ll probably leave or mabe replace it with a bandpass for 2m.
Link to pa. http://home.online.no/~la8ak/d25.htm

Geir
"J M Noeding" wrote in message
...
On Sun, 9 Jan 2005 10:04:43 +0100, "geir knutsen"
wrote:

It is an 100w pa.
Any names or numbers will help
"Gregg" wrote in message
news:xa%Dd.5345$06.2801@clgrps12...
For low power (10W), a reed relay. Else, a RF solenoid perhaps would be
in order.

for HF almost anything will work

---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm

On Sun, 9 Jan 2005 11:56:49 +0100, "geir knutsen"
wrote:

It is one of the Magnetic 8172 on your web.
The plan is to take out the circulator and place the TX relay there instead.
The LP-filter I`ll probably leave or mabe replace it with a bandpass for 2m.
Link to pa. http://home.online.no/~la8ak/d25.htm

Geir

I might have used a smaller dpdt pcb relay from LA3VW which type is
tested by LA6LCA and LA8OJ, but don't know about the availability and
type, and it is some precautions to make to make it operate properly.
The easiest is always to use PIN diode, the Unitrode UM9401 is a very
easy choice (for the series diode), and the dealer is service minded,
at least they were when I bought some. Demanded 50, but they only had
25, and I later sold most of them to friends around, hi
This type of diode may be used to at least 1kW according to SM5BSZ,
but it is a quite complex switch design to do it, normally they are
good enough for more than 100W. The smaller diode could be 2x BA182 or
2x BA282 or something better in anti-parallel. I prefer the anti-
parallel configuration even if I use some current through the diodes
during transmit

73,
JM
---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm

Do you have a link for the schematics of the PIN diode switching? or can you
send me the drafts?

Geir


"J M Noeding" wrote in message
...
On Sun, 9 Jan 2005 11:56:49 +0100, "geir knutsen"
wrote:

It is one of the Magnetic 8172 on your web.
The plan is to take out the circulator and place the TX relay there
instead.
The LP-filter I`ll probably leave or mabe replace it with a bandpass for
2m.
Link to pa. http://home.online.no/~la8ak/d25.htm

Geir

I might have used a smaller dpdt pcb relay from LA3VW which type is
tested by LA6LCA and LA8OJ, but don't know about the availability and
type, and it is some precautions to make to make it operate properly.
The easiest is always to use PIN diode, the Unitrode UM9401 is a very
easy choice (for the series diode), and the dealer is service minded,
at least they were when I bought some. Demanded 50, but they only had
25, and I later sold most of them to friends around, hi
This type of diode may be used to at least 1kW according to SM5BSZ,
but it is a quite complex switch design to do it, normally they are
good enough for more than 100W. The smaller diode could be 2x BA182 or
2x BA282 or something better in anti-parallel. I prefer the anti-
parallel configuration even if I use some current through the diodes
during transmit

73,
JM
---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm

On Mon, 10 Jan 2005 00:03:31 +0100, "geir knutsen"
wrote:

Do you have a link for the schematics of the PIN diode switching? or can you
send me the drafts?

Geir


"J M Noeding" wrote in message
.. .
On Sun, 9 Jan 2005 11:56:49 +0100, "geir knutsen"
wrote:

It is one of the Magnetic 8172 on your web.

Link to pa. http://home.online.no/~la8ak/d25.htm


I might have used a smaller dpdt pcb relay from LA3VW which type is
tested by LA6LCA and LA8OJ, but don't know about the availability and
type, and it is some precautions to make to make it operate properly.
The easiest is always to use PIN diode, the Unitrode UM9401 is a very
easy choice (for the series diode), and the dealer is service minded,
at least they were when I bought some. Demanded 50, but they only had
25, and I later sold most of them to friends around, hi
This type of diode may be used to at least 1kW according to SM5BSZ,
but it is a quite complex switch design to do it, normally they are
good enough for more than 100W. The smaller diode could be 2x BA182 or
2x BA282 or something better in anti-parallel. I prefer the anti-
parallel configuration even if I use some current through the diodes
during transmit

http://home.online.no/~la8ak/d2.htm shows several variationsin
applications for PIN diode switches, cannot remember how much direct
current is needed for your switch, it is limited by the smaller diode
D2 in fig 5
D3 is only protection for receiver if something goes wrong with the TX
switching voltage

73 jm
---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm