TS-430S Low/intermittent RX
TS-430S Low/intermittent RX
Author: Trio-Kenwood Communication, inc.
Low or intermittent receive on the TS-430S may be caused by a poor contact on one or more of the LPF relays. In most cases the following procedure will correct this problem without having to replace relays. The procedure has two steps; first initial cleaning of the contact by passing a relatively high current thru them (about 500 mA), and then installing a contact maintenance circuit that will apply a relatively low current (about 8 mA) whenever a new band is selected.
Procedure:
- [*]Initial contact cleaning procedure.
- Press and hold the "UP" bandswitch of the TS-430S (ensure the 1 MHz switch is ON).
- Apply 13.8V DC to the antenna terminal thru a 28 ohm, 10W resistor for approximately 1 minute. This will cycle thru all the relays and burn any axidation/contamination from the contacts.
- Disconnect the center lead of the coaxial cable from the antenna terminal.
- Install the contact maintenance circuit as shown in the accompanying diagrams. Attach the terminal lug strip with one of the filter unit over screws.
- Solder the 0v lead to the "JP" terminal of the Filter Unit.
Parts List:
56 ohm 5W ceramic resistor (R92-0622-05)… 2 mA[*]
Part List:Terminal Strip (E22-0371-05)
C1, C2 (CK45D2H473M) .47 µF 500V
C3 (C91-0117-05) .01 µF 50V
L1 (L33-0259-05) 470 µH
R1 (RD14CB2E102J) 1 Kohm ¼ Watt
Small length of hookup wire ………. 6 inches[*]
This procedure should may be performed only to those units received for this specific repair symptom. Time required for this procedure is 1 hour or less.
Mod talks about 28 ohm and 56 ohm resistors. Which one goes between the power supply and the radio?
As the diagram states, use either one 10 Watt 28ohm resister or two 5W 56ohm resisters.
GW1NGL W1NGL Kevin Roberts Ham Radio
Page last updated on 12/29/2011 by Kevin Roberts W1NGL a colection of Ham Radio and Electronic Information
Copyright © 2012