I'm trying to get an old-but-was-supposedly-working
consolette to run a VHF Mitrek. It worked when first
connected but is now not transmitting and also not
making any receive noise. I suspect the power supply
because it's showing 22 volts at the PS output to the
radio side and it should be around 13/14VDC. I might
have had the pass transistor(s) go bad. It's also
showing 22VDC at the transmit lamp when I hit the
PTT.
Anyway, I need to know if I'm pointed in the right
direction, and also if someone might have one of these
boatanchor power supplies I can buy.
I know I could just hook in a 20 Amp Astron supply
but the whole idea was to unkluge the Mitrek setup as it
sat on the bench, what with the control head, separate
speaker, etc.
All advice greatly appreciated.
MITREK help needed...
Moderator: Queue Moderator
-
Tom in D.C.
- Posts: 3859
- Joined: Tue Sep 04, 2001 4:00 pm
- What radios do you own?: Progreso soup can with CRT
MITREK help needed...
Tom in D.C.
In 1920, the U.S. Post Office Department ruled
that children may not be sent by parcel post.
In 1920, the U.S. Post Office Department ruled
that children may not be sent by parcel post.
-
George
- Posts: 266
- Joined: Wed Apr 16, 2003 11:14 am
- What radios do you own?: X9000, HT1550XLS, MTS2000, etc
Tom,
You do likely have shorted pass transistors.
I would suggest starting there.
The pass transistors are still available and are no problem to change.
As for the remainder of the radio, you really need a manual and hopefully your radio has not sustained any other damage.
The real question is, what is the power out rating of the radio? Did you start with a 100 watt drawer or did you remove a lower power drawer and replace it with a 100 watt drawer and now you melted the power supply?
If you wiped out lots of stuff in the drawer, I would pull your channel elements and replace the entire drawer rather than fix it as it's far more cost and time effective.
George
You do likely have shorted pass transistors.
I would suggest starting there.
The pass transistors are still available and are no problem to change.
As for the remainder of the radio, you really need a manual and hopefully your radio has not sustained any other damage.
The real question is, what is the power out rating of the radio? Did you start with a 100 watt drawer or did you remove a lower power drawer and replace it with a 100 watt drawer and now you melted the power supply?
If you wiped out lots of stuff in the drawer, I would pull your channel elements and replace the entire drawer rather than fix it as it's far more cost and time effective.
George
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Tom in D.C.
- Posts: 3859
- Joined: Tue Sep 04, 2001 4:00 pm
- What radios do you own?: Progreso soup can with CRT
Mitrek PS...
George,
Thanks for confirming my thoughts about the pass transistors.
No, I'm just running low-power radios in the drawer. Before the
thing quit I measured 35 watts out on 146.52 mHz.
I think I'll patch in my 20 amp. Astron at the bottom power block
and see if that gets the radio running again, assuming I haven't
fried it with the 22 volts!
Regards,
Thanks for confirming my thoughts about the pass transistors.
No, I'm just running low-power radios in the drawer. Before the
thing quit I measured 35 watts out on 146.52 mHz.
I think I'll patch in my 20 amp. Astron at the bottom power block
and see if that gets the radio running again, assuming I haven't
fried it with the 22 volts!
Regards,
Tom in D.C.
In 1920, the U.S. Post Office Department ruled
that children may not be sent by parcel post.
In 1920, the U.S. Post Office Department ruled
that children may not be sent by parcel post.
Blown power supply in a Consolette, very common. The pass transistors do not hold up too well to shorts or long duty cycles.
There were two basic supplies used with Mocom 70, Syntor, and Mitrek chassis, the 7 or so Amp with one pass transistor, and a 15 amp ICAS with two pass transistors in parralel. They all run over 14 volts out, even as high as 14.8 volts from the factory.
There were two basic supplies used with Mocom 70, Syntor, and Mitrek chassis, the 7 or so Amp with one pass transistor, and a 15 amp ICAS with two pass transistors in parralel. They all run over 14 volts out, even as high as 14.8 volts from the factory.
But they surely WILL notice the difference... no more total failure due to the power supply!!n5tbu wrote:Duracom switcher was my cure as well!Who cares if I cannot get 150 watts on lowband at 15 volts if I can get rated 110 on 13.8!
mod
I used the DPS 15 power supply internally for most Consoletes and the DPS 30 for the 110 watt stations.
http://www.duracomm.com/06DPSps.pdf
Other Duracomm Power Supplies that can replace the Consolete OEM's:
http://www.duracomm.com/powerblocpowersupplies.htm